“How does the Sabbath law or the Old Covenant translate into New Covenant Christianity? I read that the Catholic Church changed the Sabbath from Saturday to Sunday. Is that true?”
This has been a struggle for many Christians over the centuries. It comes from our sincere desire to obey God and please Him.
Some will say that the Catholic Church instituted the tradition of Christians worshipping on Sunday rather than Saturday. On one hand, it is true, that the "Catholic Church" did meet on Sunday rather than the typical Jewish Synagogue day being on Saturday (Sabbath). I say “Catholic Church” in the sense of the universal Church—“catholic” means “universal”—on the other hand, this is not referring to the Roman Catholic Church. But why did they meet on Sunday rather than on the Sabbath? In the early Church (during the time of the Apostles) they saw Sunday as significant in that Jesus rose from the dead on the first day of the week and so this is when they began to gather. Also the Church was born on Sunday (the day of Pentecost) when the Holy Spirit fell upon the worshiping disciples.
How do we know this?
Paul, when writing to the Corinthians, in First Corinthians 16:2 told them to set aside their offering on the first day of the week so he didn’t have to do a special collection when he came. Also Acts 20:7 tells us that they gathered together on the first day of the week to break bread. Because the resurrection happened on Sunday, that day was traditionally referred to as “The Lord’s Day” John refers to this in Revelation 1:10 to differentiate it from the Sabbath day. Christians didn’t move the Sabbath day, nor were they seeking to keep the Sabbath in the way that their Jewish brothers did.
Early Writers give us some clues to how things were in the early Church.
Pliny the Younger, an ancient Roman magistrate, wrote about the worship of the Christians and he said, “They gather early in the morning on a fixed day of the week and sing songs to Christ as to a God.” This was the practice of Christians in the first century. What day was this “fixed day?”
The Didache an early church document written AD 70 instructed the Church:
But every Lord’s day do ye gather yourselves together, and break bread, and give thanksgiving after having confessed your transgressions, that your sacrifice may be pure.
(Didache Chapter XIV.11 —Christian Assembly on the Lord’s Day. 14 [A.D. 70]).
Justin Martyr in the early second Century wrote to Trypho the Jew:
The Lawgiver is present, yet you do not see Him; to the poor the Gospel is preached, the blind see, yet you do not understand. You have now need of a second circumcision, though you glory greatly in the flesh. The new law requires you to keep perpetual sabbath, and you, because you are idle for one day, suppose you are pious, not discerning why this has been commanded you: and if you eat unleavened bread, you say the will of God has been fulfilled. The Lord our God does not take pleasure in such observances: if there is any perjured person or a thief among you, let him cease to be so; if any adulterer, let him repent; then he has kept the sweet and true sabbaths of God. If any one has impure hands, let him wash and be pure.(Dialogue with Trypho the Jew Chapter XII.—The Jews violate the eternal law, and interpret ill that of Moses.)
He also wrote:
For we too would observe the fleshly circumcision, and the Sabbaths, and in short all the feasts, if we did not know for what reason they were enjoined you,—namely, on account of your transgressions and the hardness of your hearts. For if we patiently endure all things contrived against us by wicked men and demons, so that even amid cruelties unutterable, death and torments, we pray for mercy to those who inflict such things upon us, and do not wish to give the least retort to any one, even as the new Lawgiver commanded us: how is it, Trypho, that we would not observe those rites which do not harm us, —I speak of fleshly circumcision, and Sabbaths, and feasts?(Dialogue with Trypho the Jew Chapter XVIII.—Christians would observe the law, if they did not know why it was instituted. [A.D. 155]).
“[L]et him who contends that the Sabbath is still to be observed as a balm of salvation, and circumcision on the eighth day . . . teach us that, for the time past, righteous men kept the Sabbath or practiced circumcision, and were thus rendered ‘friends of God.’ For if circumcision purges a man, since God made Adam uncircumcised, why did he not circumcise him, even after his sinning, if circumcision purges? . . . Therefore, since God originated Adam uncircumcised and unobservant of the Sabbath, consequently his offspring also, Abel, offering him sacrifices, uncircumcised and unobservant of the Sabbath, was by him [God] commended Genesis 4:1-7, Hebrews 11:4. . . Noah also, uncircumcised—yes, and unobservant of the Sabbath—God freed from the deluge. For Enoch too, most righteous man, uncircumcised and unobservant of the Sabbath, he translated from this world, who did not first taste death in order that, being a candidate for eternal life, he might show us that we also may, without the burden of the law of Moses, please God”(An Answer to the Jews Chapter II.—The Law Anterior to Moses. [A.D. 203]).
There are more quotes from early writers that tell us the Church met on the LORD’s day or the eight day but none tell us that the Christians met on the Sabbath day. The only exception to this is in the Book of Acts when the Apostles went into the Synagogue on the Sabbath day to preach the good news to their Jewish brothers. Paul always preached to the Jew first and then to the Gentiles.
We know that the Apostles had gathered on the LORD’s day Acts 2:1 on the Day of Pentecost, and Daily Acts 2:46. Something was definitely different as though every day had become a holy convocation to the LORD. They worshiped every day but saw Sunday as an important day because of the resurrection of Christ and birth of the Church.
Under the New Covenant, Christian diet changed, their worship changed, they died to who they had been and they were born again as a new creation. Early Christians, however did struggle with how they should view the Old Covenant. This came to a head when the Gentiles became part of the Church Acts 10-15. Peter was told by the Lord to eat some strange things! Unclean things! The Lord’s point was that He was opening the door to the Gentiles (Acts chapter 10.) A new day had dawned and it was becoming clear they were under a new covenant.
Once the door was open to the Gentiles, a lot of things came into question. Do the Gentiles have to keep the law of Moses to be saved? Do they have to be circumcised, do the sacrifices, observe the Sabbaths and the Holy days? This question was brought to the Church in Jerusalem (Acts 15). Many were saying that, “Yes, the Gentiles need to become Jews in order to be saved”. Peter reasoned, “Why do you test God by putting a yoke on the neck of the disciples which neither our fathers nor we were able to bear?” James, then, being the leader of the Church there, said, “Therefore I judge that we should not trouble those from among the Gentiles who are turning to God, but that we write to them to abstain from things polluted by idols, from sexual immorality, from things strangled, and from blood.” (Acts 15:19, 20).
We have to understand that this wasn’t a new “Christian Law” but rather guidelines to follow so that they would live pure lives and not offend the Jews. Is it wrong to worship God on the Sabbath? No, but it can be dangerous if you try to keep it believing that somehow God is requiring it of you or that by keeping it you can make God happy with you. It is a good idea to take one day in 7 to worship and rest. Most Christians do that on Sunday and that is OK, but it is not required.
So how should a Christian view the Sabbath? Paul wrote, “And you, being dead in your trespasses and the uncircumcision of your flesh, He has made alive together with Him, having forgiven you all trespasses, having wiped out the handwriting of requirements that was against us, which was contrary to us. And He has taken it out of the way, having nailed it to the cross. Having disarmed principalities and powers, He made a public spectacle of them, triumphing over them in it. So let no one judge you in food or in drink, or regarding a festival or a new moon or sabbaths, which are a shadow of things to come, but the substance is of Christ.”
In the book of Hebrews Chapter 4 the author argues that the Children of Israel wouldn’t enter into the rest that God intended for them. The Sabbath couldn’t bring rest, entering the promise land couldn’t bring rest, and so “there remains a rest (sabbath) for the people of God.” He concludes that rest is putting our trust in Jesus -- that Jesus is our Sabbath. Isn’t that amazing?! Jesus our true rest that God instituted clear back in Genesis!