Matthew: 60-70 AD
Mark: 55-70 AD
Luke: 55-61 AD
John: 90 AD >
These are some conservative dates for the writing of Matthew, Mark, Luke and John. Some liberal scholars prefer much later dates.
While there is uncertainty over exactly when these gospel narratives were written, it is clear that at the time of their writing the Sabbath was still part of Christian practice.
None of these New Testament books contains even the slightest suggestion that the first day of the week—the day we call Sunday—had replaced the seventh day as the Christian Sabbath.
For a look at the Sabbath practice of St. Paul see Acts 13:14-16, Acts 13:42-44, and Acts 18:1-4, 11.
There are only eight references to the first day of the week in the New Testament, and none of them contains any evidence that the significance of the Sabbath was ever transferred from one day to another. (See Matthew 28:1; Mark 16:2, 9; Luke 24:1; John 20:1, 19; Acts 20:7; 1 Corinthians 16:2.)