Introduction to the Sabbaths

1. The Law of God is for all people.

Exodus 12:49

The same law shall apply to the native as to the stranger who sojourns among you.

Exodus 22:21

You shall not wrong a stranger or oppress him, for you were strangers in the land of Egypt.

Exodus 23:9

You shall not oppress a stranger, since you yourselves know the feelings of a stranger, for you also were strangers in the land of Egypt.

Exodus 23:12

Six days you are to do your work, but on the seventh day you shall cease from labor so that your ox and your donkey may rest, and the son of your female slave, as well as your stranger, may refresh themselves.

Leviticus 19:10

Nor shall you glean your vineyard, nor shall you gather the fallen fruit of your vineyard; you shall leave them for the needy and for the stranger. I am Yehovah your God.

Leviticus 19:33-34

33 When a stranger resides with you in your land, you shall not do him wrong. 34 The stranger who resides with you shall be to you as the native among you, and you shall love him as yourself, for you were aliens in the land of Egypt; I am Yehovah your God.

Leviticus 24:22

There shall be one standard for you; it shall be for the stranger as well as the native, for I am Yehovah your God.

Leviticus 25:35

Now in case a countryman of yours becomes poor and his means with regard to you falter, then you are to sustain him, like a stranger or a sojourner, in order that he may live with you.

Numbers 15:15-16

15 As for the assembly, [2] there shall be one statute for you and for the alien who sojourns with you, a perpetual statute throughout your generations; as you are, so shall the alien be before Yehovah. 16 There is to be one law and one ordinance for you and for the alien who sojourns with you.

[2] assembly: Greek ekklesia (ἐκκλησία) translated church in the New Covenant

Deuteronomy 16:10-14

10 Then you shall celebrate the Feast of Weeks (i.e. Pentecost, Shavuot) to Yehovah your God with a tribute of a freewill offering of your hand, which you shall give just as Yehovah your God blesses you; 11 and you shall rejoice before Yehovah your God, you and your son and your daughter and your male and female servants and the Levite who is in your town, and the stranger and the orphan and the widow who are in your midst, in the place where Yehovah your God chooses to establish His name. 12 You shall remember that you were a slave in Egypt, and you shall be careful to observe these statutes. 13 You shall celebrate the Feast of Booths seven days after you have gathered in from your threshing floor and your wine vat; 14 and you shall rejoice in your feast, you and your son and your daughter and your male and female servants and the Levite and the stranger and the orphan and the widow who are in your towns.

Deuteronomy 26:12

When you have finished paying all the tithe of your increase in the third year, the year of tithing, then you shall give it to the Levite, to the stranger, to the orphan and to the widow, in order that they may eat in your towns and be satisfied.

Ruth 1:15-17 – Foreigners choose to become Yehovah's people

15 Then she said, “Behold, your sister-in-law has gone back to her people and her gods; return after your sister-in-law.” 16 But Ruth said, "Do not urge me to leave you or turn back from following you; for where you go, I will go, and where you lodge, I will lodge. Your people shall be my people, and your God, my God. 17 “Where you die, I will die, and there I will be buried. Thus may Yehovah do to me, and worse, if anything but death parts you and me.”

1 Samuel 26:6 – Foreigners fought for King David.

Then David said to Ahimelech the Hittite and to Abishai the son of Zeruiah, Joab's brother, saying, “Who will go down with me to Saul in the camp?” And Abishai said, "I will go down with you.”

1 Kings 8:41-43

41 Also concerning the foreigner who is not of Your people Israel, when he comes from a far country for Your name’s sake 42 (for they will hear of Your great name and Your mighty hand, and of Your outstretched arm); when he comes and prays toward this house, 43 hear in heaven Your dwelling place, and do according to all for which the foreigner calls to You, in order that all the peoples of the earth may know Your name, to fear You, as do Your people Israel, and that they may know that this house which I have built is called by Your name.

2 Chronicles 6:32-33

32 Also concerning the foreigner who is not from Your people Israel, when he comes from a far country for Your great name’s sake and Your mighty hand and Your outstretched arm, when they come and pray toward this house, 33 then hear from heaven, from Your dwelling place, and do according to all for which the foreigner calls to You, in order that all the peoples of the earth may know Your name, and fear You as do Your people Israel, and that they may know that this house which I have built is called by Your name.

Isaiah 56:3-8

3 Let not the foreigner who has joined himself to Yehovah say, “Yehovah will surely separate me from His people.” Nor let the eunuch say, “Behold, I am a dry tree.” 4 For thus says Yehovah, “To the eunuchs who keep My Sabbaths, and choose what pleases Me, and hold fast My covenant, 5 to them I will give in My house and within My walls a memorial, and a name better than that of sons and daughters; I will give them an everlasting name which will not be cut off. 6 Also the foreigners who join themselves to Yehovah, to minister to Him, and to love the name of Yehovah, to be His servants, everyone who keeps from profaning the Sabbath and holds fast My covenant; 7 even those I will bring to My holy mountain and make them joyful in My house of prayer. Their burnt offerings and their sacrifices will be acceptable on My altar; for My house will be called a house of prayer for all the peoples. 8 The Lord Yehovah, who gathers the dispersed of Israel, declares, “Yet others I will gather to them, to those already gathered.”

2. The Sabbath is a sign of the Covenant.

Exodus 31:13-17

13 “Speak also to the children of Israel, saying: ‘Surely My Sabbaths you shall keep, for it is a sign between Me and you throughout your generations, that you may know that I am Yehovah who sanctifies you. 14 You shall keep the Sabbath, therefore, for it is holy to you. Everyone who profanes it shall surely be put to death; for whoever does any work on it, that person shall be cut off from among his people. 15 Work shall be done for six days, but the seventh is the Sabbath of rest, holy to Yehovah. Whoever does any work on the Sabbath day, he shall surely be put to death. 16 Therefore the children of Israel shall keep the Sabbath, to observe the Sabbath throughout their generations as a perpetual covenant. 17 It is a sign between Me and the children of Israel forever; for in six days Yehovah made the heavens and the earth, and on the seventh day He rested and was refreshed.’”

Ezekiel 20:10-24

10 “Therefore, I made them go out of the land of Egypt and brought them into the wilderness. 11 And I gave them My statutes and showed them My judgments, ‘which, if a man does, he shall live by them.’ 1 2Moreover I also gave them My Sabbaths, to be a sign between them and Me, that they might know that I am Yehovah who sanctifies them. 13 Yet the house of Israel rebelled against Me in the wilderness; they did not walk in My statutes; they despised My judgments, ‘which, if a man does, he shall live by them’; and they greatly defiled My Sabbaths. Then I said I would pour out My fury on them in the wilderness, to consume them. 14 But I acted for My name’s sake, that it should not be profaned before the Gentiles, in whose sight I had brought them out. 15 So I also raised My hand in an oath to them in the wilderness, that I would not bring them into the land which I had given them, ‘flowing with milk and honey,’ the glory of all lands, 16 because they despised My judgments and did not walk in My statutes, but profaned My Sabbaths; for their heart went after their idols. 17 Nevertheless My eye spared them from destruction. I did not make an end of them in the wilderness.

18 “But I said to their children in the wilderness, ‘Do not walk in the statutes of your fathers, nor observe their judgments, nor defile yourselves with their idols. 19 I am Yehovah your God: Walk in My statutes, keep My judgments, and do them; 20 hallow My Sabbaths, and they will be a sign between Me and you, that you may know that I am Yehovah your God.’

21 “Notwithstanding, the children rebelled against Me; they did not walk in My statutes, and were not careful to observe My judgments, ‘which, if a man does, he shall live by them’; but they profaned My Sabbaths. Then I said I would pour out My fury on them and fulfill My anger against them in the wilderness. 22 Nevertheless I withdrew My hand and acted for My name’s sake, that it should not be profaned in the sight of the Gentiles, in whose sight I had brought them out. 23 Also I raised My hand in an oath to those in the wilderness, that I would scatter them among the Gentiles and disperse them throughout the countries, 24 because they had not executed My judgments, but had despised My statutes, profaned My Sabbaths, and their eyes were fixed on their fathers’ idols.

3. God details how to keep the Sabbaths.

Exodus 16:23 - Prepare work-related tasks before the Sabbaths.

Then he said to them, “This is what Yehovah has said: ‘Tomorrow is a Sabbath rest, a holy Sabbath to Yehovah. Bake what you will bake today, and boil what you will boil; and lay up for yourselves all that remains, to be kept until morning.’”

Exodus 20:8-11 - Remember the Creator and the six days of the creation week.

8 “Remember the Sabbath day, to keep it holy. 9 Six days you shall labor and do all your work, 10 but the seventh day is the Sabbath of Yehovah your God. In it you shall do no work: you, nor your son, nor your daughter, nor your male servant, nor your female servant, nor your cattle, nor your stranger who is within your gates. 11 For in six days Yehovah made the heavens and the earth, the sea, and all that is in them, and rested the seventh day. Therefore, Yehovah blessed the Sabbath day and hallowed it.

Exodus 23:12 - Don't ask others to work for you on the Sabbath.

Six days you shall do your work, and on the seventh day you shall rest, that your ox and your donkey may rest, and the son of your female servant and the stranger may be refreshed.

Exodus 34:21 - Work six days and rest on the Sabbath, even when you have more work.

Six days you shall work, but on the seventh day you shall rest; in plowing time and in harvest you shall rest.

Nehemiah 13:15-22 - Do not buy, sell, or do business in the marketplace.

15 In those days I saw people in Judah treading wine presses on the Sabbath, and bringing in sheaves, and loading donkeys with wine, grapes, figs, and all kinds of burdens, which they brought into Jerusalem on the Sabbath day. And I warned them about the day on which they were selling provisions. 16 Men of Tyre dwelt there also, who brought in fish and all kinds of goods, and sold them on the Sabbath to the children of Judah, and in Jerusalem.

17 Then I contended with the nobles of Judah, and said to them, “What evil thing is this that you do, by which you profane the Sabbath day? 18 Did not your fathers do thus, and did not our God bring all this disaster on us and on this city? Yet you bring added wrath on Israel by profaning the Sabbath.”

19 So it was, at the gates of Jerusalem, as it began to be dark before the Sabbath, that I commanded the gates to be shut, and charged that they must not be opened till after the Sabbath. Then I posted some of my servants at the gates, so that no burdens would be brought in on the Sabbath day. 20 Now the merchants and sellers of all kinds of wares lodged outside Jerusalem once or twice.

21 Then I warned them, and said to them, “Why do you spend the night around the wall? If you do so again, I will lay hands on you!” From that time on they came no more on the Sabbath. 22 And I commanded the Levites that they should cleanse themselves, and that they should go and guard the gates, to sanctify the Sabbath day.

Remember me, O my God, concerning this also, and spare me according to the greatness of Your mercy!

Isaiah 58:13-14 - Do not do your normal activities but focus on Yehovah.

13 If you turn away your foot from the Sabbath, from doing your pleasure on My holy day, and call the Sabbath a delight, the holy day of Yehovah honorable, and shall honor Him, not doing your own ways, nor finding your own pleasure, nor speaking your own words, 14 Then you shall delight yourself in Yehovah; and I will cause you to ride on the high hills of the earth, and feed you with the heritage of Jacob your father. The mouth of Yehovah has spoken.

4. The Sabbaths have specific dates.

Leviticus 23

1 Yehovah spoke again to Moses, saying, 2 “Speak to the sons of Israel and say to them, ‘Yehovah’s appointed times which you shall proclaim as holy convocations. My appointed times are these:

3 ‘For six days work may be done, but on the seventh day there is a Sabbath of complete rest, a holy convocation. You shall not do any work; it is a Sabbath to Yehovah in all your dwellings. [Sabbath = 7th day of the week]

4 ‘These are the appointed times of Yehovah, holy convocations which you shall proclaim at the times appointed for them. 5 ‘In the first month, on the fourteenth day of the month at twilight is Yehovah’s Passover. [Passover = Month 1 Day 14 at sunset] 6 ‘Then on the fifteenth day of the same month there is the Feast of Unleavened Bread to Yehovah; for seven days you shall eat unleavened bread. [Unleavened Bread = Month 1 Day 15-21] 7 ‘On the first day you shall have a holy convocation; you shall not do any laborious work. 8 ‘But for seven days you shall present an offering by fire to Yehovah. On the seventh day is a holy convocation; you shall not do any laborious work.’”

9 Then Yehovah spoke to Moses, saying, 10 “Speak to the sons of Israel and say to them, ‘When you enter the land which I am going to give to you and reap its harvest, then you shall bring in the sheaf of the first fruits of your harvest to the priest. 11 ‘He shall wave the sheaf before Yehovah for you to be accepted; on the day after the Sabbath the priest shall wave it. [Spring First Fruits = First day of the week after Passover] 12 ‘Now on the day when you wave the sheaf, you shall offer a male lamb one-year-old without defect for a burnt offering to Yehovah. 13 ‘Its grain offering shall then be two-tenths of an ephah of fine flour mixed with oil, an offering by fire to Yehovah for a soothing aroma, with its drink offering, a fourth of a hin of wine. 14 ‘Until this same day, until you have brought in the offering of your God, you shall eat neither bread nor roasted grain nor new growth. It is to be a perpetual statute throughout your generations in all your dwelling places.

15 ‘You shall also count for yourselves from the day after the Sabbath, from the day when you brought in the sheaf of the wave offering; there shall be seven complete Sabbaths.
16 ‘You shall count fifty days to the day after the seventh Sabbath; then you shall present a new grain offering to Yehovah. [Pentecost = after seven weeks (or 49 days) from spring First Fruits] 17 ‘You shall bring in from your dwelling places two loaves of bread for a wave offering, made of two-tenths of an ephah; they shall be of a fine flour, baked with leaven as first fruits to Yehovah. 18 ‘Along with the bread you shall present seven one-year-old male lambs without defect, and a bull of the herd and two rams; they are to be a burnt offering to Yehovah, with their grain offering and their drink offerings, an offering by fire of a soothing aroma to Yehovah. 19 ‘You shall also offer one male goat for a sin offering and two male lambs one-year-old for a sacrifice of peace offerings. 20 ‘The priest shall then wave them with the bread of the first fruits for a wave offering with two lambs before Yehovah; they are to be holy to Yehovah for the priest. 21 ‘On this same day you shall make a proclamation as well; you are to have a holy convocation. You shall do no laborious work. It is to be a perpetual statute in all your dwelling places throughout your generations. 22 ‘When you reap the harvest of your land, moreover, you shall not reap to the very corners of your field nor gather the gleaning of your harvest; you are to leave them for the needy and the alien. I am Yehovah your God.’”

23 Again Yehovah spoke to Moses, saying, 24 “Speak to the sons of Israel, saying, ‘In the seventh month on the first of the month you shall have a rest, a reminder by blowing of trumpets, a holy convocation. [Day of Trumpets = Month 7 Day 1] 25 ‘You shall not do any laborious work, but you shall present an offering by fire to Yehovah.’”

26 Yehovah spoke to Moses, saying, 27 “On exactly the tenth day of this seventh month is the day of atonement; it shall be a holy convocation for you, and you shall humble your souls and present an offering by fire to Yehovah. 28 “You shall not do any work on this same day, for it is a day of atonement, to make atonement on your behalf before Yehovah your God. [Day of Atonement (the Fast) = Month 7 Day 10] 29 “If there is any person who will not humble himself on this same day, he shall be cut off from his people. 30 “As for any person who does any work on this same day, that person I will destroy from among his people. 31 “You shall do no work at all. It is to be a perpetual statute throughout your generations in all your dwelling places. 32 “It is to be a Sabbath of complete rest to you, and you shall humble your souls; on the ninth of the month at evening, from evening until evening you shall keep your Sabbath.”

33 Again Yehovah spoke to Moses, saying, 34 “Speak to the sons of Israel, saying, ‘On the fifteenth of this seventh month is the Feast of Booths for seven days to Yehovah. [First day of Tabernacles = Month 7 Day 15] 35 ‘On the first day is a holy convocation; you shall do no laborious work of any kind. 36 ‘For seven days you shall present an offering by fire to Yehovah. On the eighth day you shall have a holy convocation and present an offering by fire to Yehovah; it is an assembly. You shall do no laborious work. [Tabernacles = Month 7 Day 22] 37 ‘These are the appointed times of Yehovah which you shall proclaim as holy convocations, to present offerings by fire to Yehovah -- burnt offerings and grain offerings, sacrifices and drink offerings, each day’s matter on its own day -- 38 besides those of the Sabbaths of Yehovah, and besides your gifts and besides all your votive and freewill offerings, which you give to Yehovah.  39 ‘On exactly the fifteenth day of the seventh month, when you have gathered in the crops of the land, you shall celebrate the feast of Yehovah for seven days, with a rest on the first day and a rest on the eighth day.
40 ‘Now on the first day you shall take for yourselves the foliage of beautiful trees, palm branches and boughs of leafy trees and willows of the brook, and you shall rejoice before Yehovah your God for seven days. 41 ‘You shall thus celebrate it as a feast to Yehovah for seven days in the year. It shall be a perpetual statute throughout your generations; you shall celebrate it in the seventh month. 42 ‘You shall live in booths for seven days; all the native-born in Israel shall live in booths, 43 so that your generations may know that I had the sons of Israel live in booths when I brought them out from the land of Egypt. I am Yehovah your God.’”

44 So Moses declared to the sons of Israel the appointed times of Yehovah.

Joshua 5

10 While the sons of Israel camped at Gilgal they observed the Passover on the evening of the fourteenth day of the month on the desert plains of Jericho. [Passover = Month 1 Day 14] 11 On the day after the Passover, on that very day, they ate some of the produce of the land, unleavened cakes and parched grain. [First day of Unleavened Bread = Month 1 Day 15; Spring First Fruits = First day of the week after Passover]
12 The manna ceased on the day after they had eaten some of the produce of the land, so that the sons of Israel no longer had manna, but they ate some of the yield of the land of Canaan during that year.

5. Sabbaths continue in the New Covenant.

Matthew 12:8

For the Son of Man is Lord even of the Sabbath.

Matthew 12:11-12

11 Then He said to them, “What man is there among you who has one sheep, and if it falls into a pit on the Sabbath, will not lay hold of it and lift it out? 12 Of how much more value then is a man than a sheep? Therefore, it is lawful to do good on the Sabbath.”

Matthew 24

19 But woe to those who are pregnant and to those who are nursing babies in those days! 20 And pray that your flight may not be in winter or on the Sabbath. 21 For then there will be great tribulation, such as has not been since the beginning of the world until this time, no, nor ever shall be. 22 And unless those days were shortened, no flesh would be saved; but for the elect’s sake those days will be shortened.

Mark 2:27-28

27 And He said to them, “The Sabbath was made for man, and not man for the Sabbath. 28 Therefore the Son of Man is also Lord of the Sabbath.”

Luke 23:54-56

54 That day was the Preparation, and the Sabbath drew near. 55 And the women who had come with Him from Galilee followed after, and they observed the tomb and how His body was laid. 56 Then they returned and prepared spices and fragrant oils. And they rested on the Sabbath according to the commandment.

John 7:21-24

21 Jesus answered and said to them, “I did one work, and you all marvel. 22 Moses therefore gave you circumcision (not that it is from Moses, but from the fathers), and you circumcise a man on the Sabbath. 23 If a man receives circumcision on the Sabbath, so that the law of Moses should not be broken, are you angry with Me because I made a man completely well on the Sabbath? 24 Do not judge according to appearance, but judge with righteous judgment.”

John 19:31

Therefore, because it was the Preparation Day, that the bodies should not remain on the cross on the Sabbath (for that Sabbath was a high day), the Jews asked Pilate that their legs might be broken, and that they might be taken away. 

Acts 13:42

So when the Jews went out of the synagogue, the Gentiles begged that these words might be preached to them the next Sabbath.

Acts 16:13

And on the Sabbath day we went out of the city to the riverside, where prayer was customarily made; and we sat down and spoke to the women who met there.

Acts 18:4

And he reasoned in the synagogue every Sabbath and persuaded both Jews and Greeks.

Acts 18:21

But [Paul] took leave of them, saying, “I must by all means keep this coming feast in Jerusalem; but I will return again to you, God willing.” And he sailed from Ephesus.

Acts 27:9-10

9 Now when much time had been spent, and sailing was now dangerous because the Fast [Day of Atonement on Month 7 Day 10] was already over, Paul advised them, 10 saying, “Men, I perceive that this voyage will end with disaster and much loss, not only of the cargo and ship, but also our lives.”

6. Sabbaths continue into eternity.

Isaiah 66:23

"And it shall come to pass that from one New Moon to another, and from one Sabbath to another, all flesh shall come to worship before Me,” says Yehovah.

Ezekiel 45:17

Then it shall be the prince’s part to give burnt offerings, grain offerings, and drink offerings, at the feasts, the New Moons, the Sabbaths, and at all the appointed seasons of the house of Israel. He shall prepare the sin offering, the grain offering, the burnt offering, and the peace offerings to make atonement for the house of Israel.

Zechariah 14:16

And it shall come to pass that everyone who is left of all the nations which came against Jerusalem shall go up from year to year to worship the King, Yehovah of hosts, and to keep the Feast of Tabernacles. 

7. The early church remembered the Sabbaths.

The following references are only from 1 volume of more than 10 volumes of early church writings from 100-250AD. This is not an exhaustive compilation of information regarding the Torah in early church writings but is just enough to show a clear reverence for it in the lives of early non-Jewish Christians and their interpretation of Paul, who did not write against obedience to the Law of Yehovah in the New Covenant but against the traditions and religions of men.

Christians believed the Ten Commandments (including Sabbaths) were permanent.

Preparing man for this life, the Lord Himself did speak in His own person to all alike the words of the Decalogue; and therefore, in like manner, do they remain permanently with us, receiving by means of His advent in the flesh, extension and increase, but not abrogation.¹

Christians fervently defended the Torah (including the Sabbath).

For the law commanded them to abstain from every servile work, that is, from all grasping after wealth which is procured by trading and by other worldly business; but it exhorted them to attend to the exercises of the soul, which consist in reflection, and to addresses of a beneficial kind for their neighbors’ benefit. And therefore the Lord reproved those who unjustly blamed Him for having healed upon the Sabbath-days. For He did not make void, but fulfilled the law, by performing the offices of the high priest, propitiating God for men, and cleansing the lepers, healing the sick, and Himself suffering death, that exiled man might go forth from condemnation, and might return without fear to his own inheritance.

Polycarp, a disciple of the Apostle GIĂNG and the leader of the Church of Asia, regularly led meetings on the Sabbath.

And on the Sabbath, when prayer had been made long time on bended knee, he (Polycarp), as was his custom, got up to read; and every eye was fixed upon him. Now the lesson was the Epistles of Paul to Timothy and to Titus, in which he says what manner of man a bishop ought to be.

Christians kept Passover and unleavened bread week.

“All these [Philip and his daughters, John, Polycarp, Thraseas, Sagarius, Papirius, Melito, the bishops of Asia, et. al.] observed the fourteenth day of the Passover according to the Gospel, deviating in no respect, but following the rule of faith. And I also, Polycrates, the least of you all, do according to the tradition of my relatives, some of whom I have closely followed. For seven of my relatives were bishops; and I am the eighth. And my relatives always observed the day when the people put away the leaven.”

Paul kept Pentecost.

But that Paul taught with simplicity what he knew, not only to those who were [employed] with him, but to those that heard him, he does himself make manifest. For when the bishops and presbyters who came from Ephesus and the other cities adjoining had assembled in Miletus, since he was himself hastening to Jerusalem to observe Pentecost…

Paul taught Christians to keep Passover and Pentecost.

Paul then, entering his house and gathering together the faithful there, speaks to them concerning the Passover and the Pentecost, reminding them of the New Covenant of the offering of bread and the cup; how that they ought most assuredly to celebrate it during the days of unleavened bread, but to hold fast the new mystery of the Passion and Resurrection. For here the Apostle plainly teaches that we ought neither to keep it outside the season of unleavened bread, as the heretics do, especially the Phrygians, nor yet on the other hand of necessity on the fourteenth day: for he said nothing about the fourteenth day, but named the days of unleavened bread, the Passover, and the Pentecost, thus ratifying the Gospel.

Christians did not interpret Colossians 2:16 to mean the Sabbaths were abolished, but that they should be kept in love and unity. God hates keeping Sabbaths in hypocrisy (Isaiah 1).

The apostles ordained, that “we should not judge any one in respect to meat or drink, or in regard to a feast day, or the new moons, or the Sabbaths.” Whence then these contentions? Whence these schisms? We keep the feast, but in the leaven of malice and wickedness, cutting in pieces the Church of God; and we preserve what belongs to its exterior, that we may cast away these better things, faith and love. We have heard from the prophetic words that these feasts and fasts are displeasing to the Lord.

Justin Martyr supported the change of the Sabbath to Sunday, not from direct support from Scripture, but from an allegorical interpretation of the Creation and Resurrection events.

But Sunday is the day on which we all hold our common assembly, because it is the first day on which God, having wrought a change in the darkness and matter, made the world; and Jesus Christ our Savior on the same day rose from the dead. For He was crucified on the day before that of Saturn (Saturday); and on the day after that of Saturn, which is the day of the Sun, having appeared to His apostles and disciples, He taught them these things, which we have submitted to you also for your consideration.

In Roman religion, Sunday was the day of importance. It was known as the first day of the week and the eighth day of the week. Saturday was the market day. However, to the Jews and early Christians, Saturday was the Sabbath. From the second century, some Christians in Rome compromised. They justified the move of the Sabbath to Sunday, not from direct Biblical support, but from an allegorical application of the Roman eighth day – Sunday.

And after the observance of the Sabbath, let every friend of Christ keep the Lord’s Day as a festival, the resurrection-day, the queen and chief of all the days [of the week]. Looking forward to this, the prophet declared, “To the end, for the eighth day,” on which our life both sprang up again, and the victory over death was obtained in Christ…

“Now, sirs,” I said, “it is possible for us to show how the eighth day possessed a certain mysterious import, which the seventh day did not possess, and which was promulgated by God through these rites.

The command of circumcision, again, bidding [them] always circumcise the children on the eighth day, was a type of the true circumcision, by which we are circumcised from deceit and iniquity through Him who rose from the dead on the first day after the Sabbath, [namely through] our Lord Jesus Christ. For the first day after the Sabbath, remaining the first of all the days, is called, however, the eighth, according to the number of all the days of the cycle, and [yet] remains the first.

For righteous Noah, along with the other mortals at the deluge, with his own wife, his three sons and their wives, being eight in number, were a symbol of the eighth day, wherein Christ appeared when He rose from the dead, forever the first in power.

Further, He says to them, “Your new moons and your Sabbath I cannot endure.” Ye perceive how He speaks: Your present Sabbaths are not acceptable to Me, but that is which I have made, [namely this,] when, giving rest to all things, I shall make a beginning of the eighth day, that is, a beginning of another world. Wherefore, also, we keep the eighth day with joyfulness, the day also on which Jesus rose again from the dead.

Extract from the topic of the Sabbath in Hastings Dictionary

According to church history, the seventh-day Sabbath was observed by the early church, and no other day was observed as a Sabbath during the first two or three centuries.

Extract from the topic of the Sabbath in the International Standard Bible Encyclopedia

It was during the period between Ezra and the Christian era that the spirit of Jewish legalism flourished. Innumerable restrictions and rules were formulated for the conduct of life under the Law. Great principles were lost to sight in the mass of petty details. Two entire treatises of the Mishna, Shabbāth and ‛Ērūbhı̄n, are devoted to the details of Sabbath observance. The subject is touched upon in other parts of the Mishna; and in the Gemara there are extended discussions, with citations of the often divergent opinions of the rabbis. In the Mishna (Shahbāth, vii. 2) there are 39 classes of prohibited actions with regard to the Sabbath, and there is much hair-splitting in working out the details. The beginnings of this elaborate definition of actions permitted and actions forbidden are to be found in the centuries immediately preceding the Christian era. The movement was at flood tide during our Lord’s earthly ministry and continued for centuries afterward, in spite of His frequent and vigorous protests.

All are agreed that Christ and His disciples observed the seventh-day Sabbath previous to the crucifixion. That His followers had received no intimation of any proposed change at His death, is evident from the recorded fact that on the day when He was in the tomb they rested, “on the sabbath ... according to the commandment” (Luke 23:56); and that they treated the following day, the first day of the week, the same as of old, is further evident, as upon that day they came unto the sepulcher for the purpose of anointing the body of Jesus. In the Book of Acts, which gives a brief history of the work of the disciples in proclaiming the gospel of a risen Savior, no other Sabbath is recognized than the seventh day, and this is mentioned in the most natural way as the proper designation of a well-known institution (Acts 13:14, 13:27, 13:42, 16:13, 18:4).

In our Lord’s great prophecy, in which He foretold the experience of the church between the first and the second advent, He recognized the seventh-day Sabbath as an existing institution at the time of the destruction of Jerusalem (70 AD), when He instructed His disciples, “Pray ye that your flight be not in the winter, neither on a sabbath” (Matthew 24:20). Such instruction given in these words, and at that time, would have been confusing in the extreme, had there been any such thing contemplated as the overthrow of the Sabbath law at the crucifixion, and the substitution of another day upon an entirely different basis.

That the original Sabbath is to be observed, not only during the present order of things, but also after the restoration when, according to the vision of the revelator, a new heaven and a new earth will take the place of the heaven and the earth that now are, is clearly intimated in the words of the Lord through the prophet Isaiah: “For as the new heavens and the new earth, which I will make, shall remain before me, saith Yehovah, so shall your seed and your name remain. And it shall come to pass, that from one new moon to another, and from one sabbath to another, shall all flesh come to worship before me, saith Yehovah” (Isaiah 66:22-23).

¹ Irenaeus. (trans. 1867). Against Heresies (Book 4, chapter 16:4). In Philip Shaff, Ante-Nicene Fathers (Vol. 1, p. 785). Retrieved from http://www.ccel.org/node/70