Let us look briefly through the New Testament to find which day Paul kept and taught Gentile converts to keep.
1. Acts 13:14-15, 42-44: "But when they departed from Perga, they came to Antioch in Pisidia, and went into the synagogue on the Sabbath day, and sat down. And after the reading of the Law and the Prophets, the rulers of the synagogue sent to them, saying, 'Men and brethren, if you have any word of exhortation for the people, say on.'"
Then Paul stands up and preaches the gospel to them. "And when the Jews went out of the synagogue, the Gentiles begged that these words might be preached to them the next Sabbath" (verse 42). Since Paul was preaching "the grace of God" (verse 43), here is his opportunity to explain to these Gentiles that the Sabbath was done away. But he does no such thing.
Why should he wait a whole week to preach to the Gentiles on the next Sabbath? If the day of worship had been changed to Sunday, why did Paul not tell them they would not have to wait a week, but the very next day, Sunday, was the proper day of worship?
Instead, "And the next Sabbath almost the whole city came together to hear the word of God" (verse 44). Here Paul waits a whole week, passing up a Sunday, to preach to the Gentiles on the Sabbath.
2. Acts 15:1-2, 14-21: Certain men had come from Judea to Antioch, teaching that the Gentile converts must be circumcised and keep the law of Moses to be saved. Paul and Barnabas vigorously contested this teaching. It was decided, then, that Paul and Barnabas should go to Jerusalem to seek counsel of the apostles and elders on this matter.
At the conference at Jerusalem, James gives the decision: "Therefore I judge . . . that we write to them to abstain from things polluted by idols, from sexual immorality, from things strangled, and from blood" (verses 19-20). Notice he does not say they should not keep the Ten Commandments—they were not even in question—but only the rite of circumcision, which is an altogether different law. He merely prohibits four common practices of Gentile religion.
James continues, "For Moses has had throughout many generations those who preach him in every city, being read in the synagogues every Sabbath" (verse 21). The writings of Moses were taught in the synagogues every Sabbath. Attendees heard God's law expounded every Sabbath and did not need further instruction. The apostles wrote this concise judgment, then, because Gentile converts attended church on the Sabbath and thus already knew what to keep! In addition, the apostles' letter does not reprove them in any way for keeping the Sabbath.
3. Acts 16:12-15: Paul and Silas arrive in Philippi. "And we were staying in that city for some days. 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. Now a certain woman named Lydia heard us. She was a seller of purple from the city of Thyatira, who worshipped God. The Lord opened her heart to heed the things spoken by Paul. And . . . she and her household were baptized. . . ."
Here again Paul and his companions waited until the Sabbath, and then went to a place of worship and preached. This woman, probably a Gentile, was converted. The passage says it was customary to meet there on the Sabbath, just as it was Paul's custom to go to a place of prayer and worship when the Sabbath day came.
4. Acts 18:1-11: "After these things Paul departed from Athens and went to Corinth. And found a certain Jew named Aquila . . . with his wife Priscilla . . . and he came to them. So, because he was of the same trade, he stayed with them and worked; for by occupation they were tentmakers. And he reasoned in the synagogue every Sabbath, and persuaded both Jews and Greeks."
If we could find one New Testament text giving as strong authority for Sunday observance as this one does for keeping the Sabbath, we would certainly have Bible authority for it! Here Paul worked weekdays, but went to church and taught Gentiles as well as Jews every Sabbath.
He preached the gospel of the Kingdom, but when the Jews became offended and blasphemed, he turned away from the Jews altogether. From then on he preached only to Gentiles (verse 6). He continued there a year and six months (verse 11), working weekdays and preaching every Sabbath just to the Gentiles!
To these Gentiles of Corinth, Paul commanded: "Imitate me, just as I also imitate Christ" (I Corinthians 11:1). "Paul, as his custom was, went in to them, and for three Sabbaths reasoned with them from the Scriptures" (Acts 17:2). It was his customary practice to keep the Sabbath, as the Bible proves by its recording of eighty-four different Sabbaths Paul kept.
Did he imitate Jesus in this? Indeed! Jesus, "as His custom was . . . went into the synagogue on the Sabbath day" (Luke 4:16). Keeping the Sabbath was Jesus' custom. Paul followed Him, and commanded Gentile converts to follow him, just as he followed Christ. Should we not do the same?
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