Why Should Christians Celebrate the Passover?

The first of God's seven annual festivals is the Passover (Leviticus 23:5). Passover falls in early spring in the Holy Land and is a reminder of how God spared His people from death in Egypt. To rescue His people from slavery, God took the lives of all the firstborn Egyptian males (Exodus 12:7, 26-29) but passed over the Israelites' homes that had the blood of a sacrificed lamb on their door frames.
The blood of the Passover lamb foreshadowed the sacrifice of Jesus Christ, which passes over the sins of people who repent in order to spare them from eternal death. The New Testament makes clear that Christ is the true Passover Lamb (compare Exodus 12:21 with 1 Corinthians 5:7). In observing His last Passover with His disciples, Jesus explained that the symbols of bread and wine represent His body and blood, offered by Him for the forgiveness (or passing over) of our sins and the death penalty our sins have earned for us (Matthew 26:26-28; Mark 14:22-24).
The death of Christ actually took place during the daylight hours that followed the Passover evening—which was still the same date according to Hebrew sunset-to-sunset reckoning. Christ was sacrificed on Passover.
The New Testament Passover is a memorial of the suffering and death of Jesus Christ. This is also when baptized members of the United Church of God renew our agreement to come under the blood of Jesus Christ, the perfect Passover Lamb, for the forgiveness of our sins. We approach this period of the year with deep spiritual introspection. We commemorate the Passover on the 14th day of the first month of the sacred year with a service based on the instructions of 1 Corinthians 11:23-28 and the Gospel accounts of the New Testament Passover that Christ instituted.
This solemn service begins with a brief explanation of its purpose, followed by foot-washing (based on Christ's example and instructions in John 13). Then the minister gives an explanation of the symbols of the Passover, unleavened bread and wine, which represent the body and blood of our Savior. Each baptized member of the Church eats a small piece of the unleavened bread and drinks a small glass of the wine (Mark 14:22-24).
Christians who observe this annual memorial marking Jesus' death (1 Corinthians 11:26) are reminded that eternal life is possible only through Him (John 6:47-54; Acts 4:10-12). Jesus' sacrifice is the starting point for salvation and the foundation of the annual feast days that follow. The next one is the Feast of Unleavened Bread.