The Feast of Passover is first mentioned in Exodus 12 where God instructed the Israelites to select a lamb (or a kid goat) without blemish, kill it on the 14^th day of the first month, put some of its blood on the doorposts and lintel and roast and eat it that same night.  God killed the firstborn of man and beast in every household that did not have the Passover lamb’s blood on it.

The Feast of Passover is also mentioned in Leviticus 23, which lists all the Feasts of the Lord.

Lev 23:5 On the fourteenth day of the first month at twilight is the LORD’s Passover.

The slaughtered innocent lamb whose shed blood saved the Israelites from death clearly portrays Jesus Christ who shed His innocent blood that we might live.  Indeed, 1 Corinthians 5:7 states that Christ is our Passover. 

1Co 5:7  … For indeed Christ, our Passover, was sacrificed for us.

Thus we can conclude that the Feast of Passover (with its sacrificial lamb) pictures the death and sacrifice of our saviour Jesus Christ.  

However, there is more than can be said of the Passover.  Jesus introduced the symbols of the new covenant on the Passover.  The night before Jesus’s fulfilment of the Passover lamb by being crucified for our sins, Jesus kept the Passover with His disciples, and then introduced new symbols of bread and wine, which He instructed us to partake of.

Luk 22:14  When the hour had come, He sat down, and the twelve apostles with Him.
Luk 22:15  Then He said to them, “With fervent desire I have desired to eat this Passover with you before I suffer;
Luk 22:16  for I say to you, I will no longer eat of it until it is fulfilled in the kingdom of God.”

Luk 22:19  And He took bread, gave thanks and broke it, and gave it to them, saying, “This is My body which is given for you; do this in remembrance of Me.”
Luk 22:20  Likewise He also took the cup after supper, saying, “This cup is the new covenant in My blood, which is shed for you.

The instruction is repeated in 1 Corinthians.

1Co 11:23  For I received from the Lord that which I also delivered to you: that the Lord Jesus on the same night in which He was betrayed took bread;
1Co 11:24  and when He had given thanks, He broke it and said, “Take, eat; this is My body which is broken for you; do this in remembrance of Me.”
1Co 11:25  In the same manner He also took the cup after supper, saying, “This cup is the new covenant in My blood. This do, as often as you drink it, in remembrance of Me.”

The bread pictures Christ’s broken body, given for us; and the cup (of wine) pictures the new covenant in Christ’s shed blood.

The bread and wine should be taken once a year, see, “How often should “the Lord’s Supper” be taken?” 

What about eating a Passover lamb?  There is no indication that this is necessary now.  Perhaps what Jesus said in Luke 22:16, “I will no longer eat of it until it is fulfilled in the kingdom of God”, indicates that in the kingdom of God people will eat a Passover lamb as they did before the first coming of the Messiah.  We will have to wait and see.

Conclusion

The Feast of Passover (with its sacrificial lamb) pictures the death and sacrifice of our saviour Jesus Christ.