Question: "What is biblical typology?"
Answer: Typology is a special kind of symbolism. (A symbol is something that represents something else.) We can define a type as a “prophetic symbol” because all types are representations of something yet future. More specifically, a type in Scripture is a person or thing in the Old Testament that foreshadows a person or thing in the New Testament. For example, the flood of Noah’s day (Genesis 6—7) is used as a type of baptism in 1 Peter 3:20–21. The word for “type” that Peter uses is figure.
When we say that someone is a type of Christ, we are saying that a person in the Old Testament behaves in a way that corresponds to Jesus' character or actions in the New Testament. When we say that something is "typical" of Christ, we are saying that an object or event in the Old Testament can be viewed as representative of some quality of Jesus.
Scripture itself identifies several Old Testament events as types of Christ's redemption, including the tabernacle, the sacrificial system, and the Passover. The Old Testament tabernacle is identified as a type in Hebrews 9:8-9: "the first tabernacle . . . which was a figure for the time then present." The high priest's entrance into the holiest place once a year prefigured the mediation of Christ, our High Priest. Later, the veil of the tabernacle is said to be a type of Christ (Hebrews 10:19-20) in that His flesh was torn, (as the veil was when He was crucified) in order to provide entrance into God's presence for those who are covered by His sacrifice.
The whole sacrificial system is seen as a type in Hebrews 9:19-26. The articles of the "first testament" were dedicated with the blood of sacrifice; these articles are called "the patterns of things in the heavens" and "figures of the true" (verses 23-24). This passage teaches that the Old Testament sacrifices typify Christ's final sacrifice for the sins of the world. The Passover is also a type of Christ, according to 1 Corinthians 5:7, "Christ our passover is sacrificed for us." Discovering exactly what the events of the Passover teach us about Christ is a rich and rewarding study.
We should point out the difference between an illustration and a type. A type is always identified as such in the New Testament. A Bible student finding correlations between an Old Testament story and the life of Christ is simply finding illustrations, not types. In other words, typology is determined by Scripture. The Holy Spirit inspired the use of types; illustrations and analogies are the result of man's study. For example, many people see parallels between Joseph (Genesis 37-45) and Jesus. The humiliation and subsequent glorification of Joseph seem to correspond to the death and resurrection of Christ. However, the New Testament never uses Joseph as a model of Christ; therefore, Joseph's story is properly called an illustration, but not a type, of Christ.