A.T. Robertson Commentary Luke 23:54

"And it was the day of the Preparation, and the sabbath drew on." — Luke 23:54 (ASV)

The day of the Preparation (ημερα παρασκευης). The technical Jewish phrase for the day before the sabbath for which see discussion on Mt 27:62.

Drew on (επεφωσκεν). Imperfect active, began to dawn or give light. However, it was sundown, not sunrise when the Jewish sabbath (twenty-four-hour day) began. The confusion is to us, not to the Jews or the readers of the Greek New Testament. Luke is not speaking of the twelve-hour day which began with sunrise, but the twenty-four-hour day which began with sunset.