We are taking a look at the feasts of Israel because in them is laid the prophetic foundation for the identity of the Messiah. The name Messiah is simply the English transliteration of the Hebrew word which refers to the same person as our word Christ. So, we are looking at the feasts in order to establish whether Jesus of Nazareth, of 4 B.C.-33 A.D. fame, is the Jewish Messiah. This look is important for a couple of reasons. First, the Hebrew Messiah is destined to be the final Judge of all the earth; and second, the issue of Christianity is the issue of whether Jesus is that Messiah, or whether the entire Christian world has been founded upon a huge mistake.
This is where the prophetic foundation comes into play. Rationally, fulfilled prophecy is the cornerstone of religious truth. In the Old Testament, people knew and understood that if a prophet could accurately predict the future consistently, he was in touch with the true omniscient God. In the New Testament it is likewise a given that He who fulfilled the ancient prophecies is the Christ, and He that is the Christ will one day confront, in judgment, every human being ever conceived. There is no flaw in this rational base. The only thing that needs to be examined is whether the prophecies were actually fulfilled by Jesus.
Thus, in the feast of Passover, the first major prophetic picture was drawn. That picture was of a doctrine: salvation by the blood of an innocent lamb/ram instead of salvation by good human performance. Israel wasn't being particularly good in their bondage in Egypt. (036) They hadn't been particularly good before they went into Egypt. And their record after the deliverance from Egypt wasn't particularly good. Israel was saved from Egypt because God had set His love upon her. Why He had done so isn't always very clear in the Bible, but that He had done so is without question. The way of salvation develops from that reality. God saves people because He loves them, not because they are good.
But, the way of salvation is the main question. How is a man to be saved? The Feast of Passover shows us: by the blood of an innocent lamb, shed in the place of a guilty sinner. In other words, salvation is by substitution: the sinner is offered a personal substitute which will pay the debt he owes, in his place. So, is Jesus of Nazareth an honest-to-goodness fulfillment of that picture? Well, when he came on the scene of history, He was immediately identified by prophetic utterance as "The Lamb of God who takes away the sin of the world" (John 1:29).
Did He live up to His billing? The Scriptures tell us that even His enemies were unable to bring a valid charge of sin against Him (this was attested to by a legitimate Roman court). He lived His life in such a way that even his own brothers, who didn't believe in Him at first, were unable to lay a charge of sin against Him--and they lived in the same home with Him for 30 years! So, the record is that He was a Lamb from God and He lived sinlessly. At this level, at least, He fit the bill--an innocent victim to die in the place of guilty sinners.