Luk 22:14 And when the hour was come, he sat down, and the twelve apostles with him.
Luk 22:15 And he said unto them, With desire I have desired to eat this passover with you before I suffer:
Passover Lamb was killed on the 14th.
Exo 12:6 And ye shall keep it up until the fourteenth day of the same month: and the whole assembly of the congregation of Israel shall kill it in the evening.
Just like the feast of unleavened bread began the evening of the 14th.
Luk 22:7 Then came the day of unleavened bread, when the passover must be killed.
Luk 22:8 And he sent Peter and John, saying, Go and prepare us the passover, that we may eat.
Luk 22:9 And they said unto him, Where wilt thou that we prepare?
Luk 22:10 And he said unto them, Behold, when ye are entered into the city, there shall a man meet you, bearing a pitcher of water; follow him into the house where he entereth in.
Luk 22:11 And ye shall say unto the goodman of the house, The Master saith unto thee, Where is the guestchamber, where I shall eat the passover with my disciples?
I'm not trying to load the forum with post, but I thought these scriptures should assist you in understanding.
1Co 5:7 Purge out therefore the old leaven, that ye may be a new lump, as ye are unleavened. For even Christ our passover is sacrificed for us:
1Co 5:8 Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness; but with the unleavened bread of sincerity and truth.
As Paul said, so say I... Let us keep the feasts, even as Christ did. For as often as we do this (keep the feast), we proclaim His death (the passover lamb, slain for the sins of the world) until He returns. Amen...
Love Always,