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The Christians during the apostolic era (basically the first century, from about 35 to 100 A.D.) kept Sabbath on the seventh day of the week, more or less what we now call Saturday. (More or less" because the Bible Sabbath begins and ends at sundown whereas Saturday begins and ends at midnight). For the first 300 years of Christian history, the Christian religion was an illegal religion, but Judaism was a legal religion. During the apostolic era, Christians found it convenient to let the Roman authorities think of them as Jews. Sabbath observance is quite visible.

There are no New Testament texts that say God, Jesus, or the apostles changed the Sabbath to Sunday. This is very significant, and we will explain why.