Dr. Bacchiocchi argues that the description of the earliest Christian gatherings indicate a continuity between Judaism and Christianity and not discontinuity. This is one of the strongest arguments for the continuing validity of the Sabbath for Christians.
Synagogue Primary Place of Worship of Early Christian Community
In Acts, Luke (Luke and Acts) describes the synagogue as a place where early Christian worship took place. Luke writes, in Acts 18:24-26, that Apollos preached about Jesus in the synagogue.
When Paul went searching for Christians to imprison them, he went to the synagogues (Acts 9:2; Acts 22:19). Paul continued his habitual Sabbath-keeping after conversion for Luke identifies Paul’s habit of Sabbath-keeping as a “custom.â€
Jews and Gentiles Wanting to Worship on the Sabbath
At Pisidian Antioch they went to the Synagogue and sat amongst the worshippers (Acts 13:14). The synagogue leaders asked them to speak. This further confirms that Christian believers did not experience a radical separation from their Jewish brothers and sisters.
It is here that Paul and his companions were invited to come back and the “next Sabbath” almost the whole town came back to hear them. We must note that the group that came to hear him was both “Jews and Gentiles.” Why didn’t Paul tell those Gentile believers to come hear us tomorrow, which would have been Sunday, if Sunday did have an apostolic origin?
We also see this in Corinth where both Jews and Greeks were convinced of the Gospel of Jesus Christ. And these meetings happened on the Sabbath in the synagogue (Acts 18:4).
Outdoor Sabbath Worship
Even when they were not in the synagogue, Paul and his companions found worshipers. So they went to a place where they thought there would be some Sabbath Prayer Warriors (“where we expected to find a place of prayer”). And they found such a place down by a riverside. When you sing the song, “Gonna Lay down My Burdens, down by the riverside,” you are bringing to mind these early Seventh day Sabbath meetings. (Acts 16:13)
Conclusion
The idea that there was a radical break between Judaism and Christianity is not in line with the evidence presented by Luke in the book of Acts. Early Christians were a group of Jews who believed that Jesus was the long-anticipated Messiah. Because of this, they came and worshiped at the synagogue on the Sabbath day.