Question: Why do Christians generally consider the Sabbath to run from midnight to midnight while the Jewish tradition is from Friday evening to Saturday evening?
Answer: Actually, whether to begin the Sabbath at sundown or at midnight is something that is not stated in our confession and there are some believers that do observe from sundown to sundown. This has warrant because in scripture because from the very beginning you have God at creation declaring “so the evening and the morning were the first day (evening comes first),” and likewise about each day. They are all said to begin at evening.
But there is a cultural component here. In our society, we are culturally conditioned to look at the new day as beginning at midnight . The Romans did the same in the time of Jesus. Some of the believers in the early church who were slaves went to church early in the morning because they had to work after the sun came up, and then went again in the evening after the sun went down, on what we would call the same day and on what the Jews would technically call the next day. This would correspond with Jesus’ resurrection (early in the morning on Sunday) and with His visit with the disciples on the evening of the same day. John is very deliberate in his language when he says in John 20:19: “Then, the same day at evening being the first day of the week...” In other words, John used the reckoning of the Romans to suggest that it was still the first day of the week at evening. This would point to the observance of the day from midnight to midnight. Because of John’s emphasis on this, I am inclined to prefer this view.
However, because there is warrant for both views, it has not been a matter of great contention in the church. I think that it is not a bad practice to sort of do both evenings—in other words, to use Saturday evening to prepare for worship, and then to use Sunday evening to look back on the day with thankfulness and close out the day with the Lord. After all, there is a pattern in scripture of morning and evening prayers every day (closing out the day with the Lord), so in preparation for the Lord’s Day, one can take extra time on Saturday.