The first day of the festival of Unleavened Bread is when the Passover lamb is sacrificed. Jesus called Peter and John to him, saying “Go and prepare the Passover meal for us.” They asked “Where shall we do this?”
He said “A man carrying a water jug will meet you when you go into the city. Follow him into the house he enters. Tell the owner of that house ‘The Teacher says “My time is at hand, so I ask where your guestroom is so that I may celebrate the Passover meal with my disciples.” He will then show you a large furnished room upstairs ready to use. That is where you should prepare for our dinner.”
Peter and John left and found everything exactly as Jesus had told them, and they prepared the Passover meal.
MT 26:17-19, MK 14:12-16, LK 22:7-13