Jesus was crucified on the day of preparation for the Passover -- the day before the Passover meal was eaten.
Now before the feast of the passover ... And supper being ended, the devil having now put into the heart of Judas Iscariot, Simon's son, to betray him. John 13:1-2
And it was the preparation of the passover, and about the sixth hour: and he saith unto the Jews, Behold your King! But they cried out, Away with him, away with him, crucify him. Pilate saith unto them, Shall I crucify your King? The chief priests answered, We have no king but Caesar. Then delivered he him therefore unto them to be crucified. John 19:14-16
Jesus and his disciples prepared for and ate the passover meal together. The "last supper" was their Passover meal.
Now the first day of the feast of unleavened bread the disciples came to Jesus, saying unto him, Where wilt thou that we prepare for thee to eat the passover? ... And the disciples did as Jesus had appointed them; and they made ready the passover. Matthew 26:17
And the first day of unleavened bread, when they killed the passover, his disciples said unto him, Where wilt thou that we go and prepare that thou mayest eat the passover? Mark 14:12
Then came the day of unleavened bread, when the passover must be killed. And he sent Peter and John, saying, Go and prepare us the passover, that we may eat. Luke 22:7-8
