John Calvin Commentary Matthew 26:20

"Now when even was come, he was sitting at meat with the twelve disciples;" — Matthew 26:20 (ASV)

When the evening was come, he sat down at table. Not to eat the passover, which they were bound to do standing (as travelers, when they are in haste, are accustomed to take food hastily, with shoes on their feet, and a staff in their hand, Exodus 12:11); but I consider the meaning to be that after having observed the solemn rite, he sat down at table to supper.

Accordingly, the Evangelists say, when the evening was come: for, at the commencement of the evening, they killed the lamb and ate its roasted flesh.