Turretinfan and rested the seventh day: wherefore the Lord blessed the sabbath day, and hallowed it.
Deuteronomy 5:15 And remember that thou wast a servant in the land of Egypt, and that the Lord thy God brought thee out thence through a mighty hand and by a stretched out arm: therefore the Lord thy God commanded thee to keep the sabbath day.
However, Christ Jesus did a new work of Creation and Redemption and completed that on the first day of the week, when he arose from grave. Accordingly, since that time, believers have gathered for worship on the first of the seven, rather than on the seventh of the seven.
We see this is in the positive example of the apostles:
John 20:19 Then the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled for fear of the Jews, came Jesus and stood in the midst, and saith unto them, Peace be unto you.
Acts 20:7 And upon the first day of the week, when the disciples came together to break bread, Paul preached unto them, ready to depart on the morrow; and continued his speech until midnight.
1 Corinthians 16:2 Upon the first day of the week let every one of you lay by him in store, as God hath prospered him, that there be no gatherings when I come.
We also see this in the negative example of the apostles, namely that they did outreach to the Jews on the Jewish Sabbath:
Acts 13:14 But when they departed from Perga, they came to Antioch in Pisidia, and went into the synagogue on the sabbath day, and sat down.
Acts 13:42 And when the Jews were gone out of the synagogue, the Gentiles besought that these words might be preached to them the next sabbath.
Acts 16:13 And on the sabbath we went out of the city by a river side, where prayer was wont to be made; and we sat down, and spake unto the women which resorted thither.
Acts 17:2 And Paul, as his manner was, went in unto them, and three sabbath days reasoned with them out of the scriptures,
Acts 18:4 And he reasoned in the synagogue every sabbath, and persuaded the Jews and the Greeks.