Christ's blood is the only blood God allows us to consume - indeed, we must consume it, for it is the guarantee of eternal life. Jesus explains this in John 6:53-57, which I will read:
The eating and drinking relate to something that is ongoing rather than something that is past. Jesus has already fulfilled the sin offering, and the individual would not eat or drink of it anyway. But the spiritual life - the abundance - pictured in the bread and wine is something we experience as we look forward to the future with great hope because of the covenant and what God promises to do within it. The verbs, eat, drink, eats, drinks, abides, and feeds in this passage are in the present tense, meaning that we do them on a continual basis. Our eating and drinking of Christ describe our relationship with Him.
John 6:57 in J.B. Phillips' translation reads, The man who eats [M]y body and drinks [M]y blood shares [M]y life and I share his. The life He gives us imparts the true well-being and fulfillment that this world cannot give. The Passover is a commemoration of the abundant, eternal life that God has graciously made available to us, which will find its culmination when the Passover is fulfilled at Christ's return.
Jesus Christ's body is a multi-faceted symbol. Sometimes Christ's body is a symbol of His death, but at other times it is a symbol of life. So, it says here that the Passover bread represents Christ's body. When Jesus uses bread as a symbol for His body, it is a symbol of life, even eternal life. We won't turn to it, but John 6 explains this symbol very clearly. There, Jesus speaks of bread that endures to everlasting life. He speaks of the bread of God, the bread of life, and the living bread. When Jesus says that He is the living bread (John 6:51), it means that His flesh is not merely something that leads to eternal life, but He indicates a body that is alive. As we partake of the bread, we become one with the living Savior.
Certainly that ought to point out to us the importance of the Passover, because we understand that He is speaking symbolically (figuratively) of His own death, His burial, and His resurrection. And that these symbols would be part and parcel of the way of life that He gave to us—something with which we would be renewing our commitment to Him and to His Father.
I think that summarizes. It points out the importance of the Passover to you and me. If we do not take the Passover, and take it properly; we simply have no eternal life in us. It is just that important!
In Exodus 12, if those people had not followed the instructions—I want you to note this. They had to eat the Passover. The emphasis here is on "eating." We may go so far as to say that the eating of the Passover might be the most important part of all. Anybody can begin by believing in the Word of God—believing in the sacrifice of Jesus Christ. "Eating" and "drinking" implies a lifelong process! That shows whether the person really is "a Christian."
