Romans 14 in the New Testament discusses the observance of days. The Christian church in Rome was originally comprised of Jewish believers. In 54 A.D. the Jews were expelled from Rome. Aquilla and Priscilla were among the Jewish exiles (Acts 18:2). The Jews returned to Rome a few years later. During the exile from Rome, the Christian church was made up of Gentile believers. They had not a strong Mosaic background as did the Jews; consequently, when the Jews returned, there was conflict between the Jewish and Gentile Christians over various issues. Observance of the 7th day Sabbath would have been included in those issues. Paul did not say the Sabbath had been abrogated, like circumcision. He said simply that we should not judge each other when matters of conscience are involved. The Jews had very strong convictions about the Sabbath. The Gentiles did not; however, salvation is found through faith in Christ’s death and resurrection and the forgiveness of sin, not through the observance of any law. At that early stage of Christian belief, that’s what Paul wanted to focus on– Jesus. The Sabbath remains blessed and sanctified. Those of us who observe it are rewarded; however, It was not to be a cudgel against Christian believers who did not share that conviction. In Romans 12, Paul was more concerned about dietary issues than the observance of one day above another. He allowed individuals who believed in Christ to eat what their conscience allowed. In the same manner, at that time, he left the observance of one day above another to the individual.

Acts 5:29
Then Peter and the other apostles answered and said, We ought to obey God rather than men.

1 Cor. 11:23-26
For I have received of the Lord that which also I delivered unto you, That the Lord Jesus the same night in which he was betrayed took bread: [24] And when he had given thanks, he brake it, and said, Take, eat: this is my body, which is broken for you: this do in remembrance of me. [25] After the same manner also he took the cup, when he had supped, saying, This cup is the new testament in my blood: this do ye, as oft as ye drink it, in remembrance of me. [26] For as often as ye eat this bread, and drink this cup, ye do shew the Lord’s death till he come.