Albert Barnes Commentary Matthew 27:62

"Now on the morrow, which is [the day] after the Preparation, the chief priests and the Pharisees were gathered together unto Pilate," — Matthew 27:62 (ASV)

Now the next day, that followed the day of the preparation. The first day of the feast of the Passover was called the day of preparation, because all things were on that day gotten ready for the observances of the Paschal week. The Jewish day closed at sunset, and the Sabbath at that time commenced.

The next day mentioned here does not mean the following day in our understanding of the term, or the following morning, but the next day in the Jewish way of speaking; that is, after the next day had commenced, or after sundown. To suppose them to have waited until the next morning would be absurd, as the disciples would be as likely to steal him away the first night as the second.