The following is an excerpt from The MacArthur New Testament Commentary on Hebrews 7.

For this Melchizedek, king of Salem, priest of the Most High God, who met Abraham as he was returning from the slaughter of the kings and blessed him, to whom also Abraham apportioned a tenth part of all the spoils, was first of all, by the translation of his name, king of righteousness, and then also king of Salem, which is king of peace. Without father, without mother, without genealogy, having neither beginning of days nor end of life, but made like the Son of God, he abides a priest perpetually. (7:1–3)In biblical study, a type refers to an Old Testament person, practice, or ceremony that has a counterpart, an antitype, in the New Testament. In that sense types are predictive. The type pictures, or prefigures, the antitype. The type, though it is historical, real, and of God, is nonetheless imperfect and temporary. The antitype, on the other hand, is perfect and eternal. The study of types and antitypes is called, as one might expect, typology.

The bronze serpent that God commanded Moses to set on a standard (Num. 21:8), for example, was a type of Christ’s being lifted up on the cross (John 3:14). The sacrificial lamb was a type of the Lamb of God, Jesus Christ, who was sacrificed for the sins of the world (John 1:29; Rev. 5:6, 8; etc.).

Melchizedek is also a type of Christ. As mentioned earlier, the Bible gives very little historical information about Melchizedek. All that we know is located in Genesis 14, Psalm 110, and Hebrews 5–7. The most detailed information is in Hebrews 7:1–3.

Types are frail illustrations at best. They are analogies, and, like all analogies, they correspond to the person or thing to which they are compared only in certain ways—perhaps only in one way. The bronze serpent typified Christ in that it was lifted up for all the people to see and in that looking upon it brought them deliverance. The sacrificial lamb typifies Christ in that it is very meek (innocent) and that it was sacrificed on behalf of the sins of another. Similarly, though Melchizedek is in no way the equal of Christ, his unique priesthood, and even his name, typify Jesus Christ and His work in a number of significant ways.

Chapter 7 is the focal point of Hebrews. It concerns the central, the most important, part of Judaism—the priesthood. No sacrifices could be made except by the priest and no forgiveness of sins could be had apart from the sacrifices. Obedience to the law was exceedingly important, but the offering of sacrifices was even more important. And the priesthood was essential for offering them. Consequently, the priesthood was exalted in Judaism.

The law God gave Israel was holy and good, but because the Israelites, as all men, were sinful by nature, they could not keep the law perfectly. When they broke the law, fellowship with God was also broken. The only way of restoring fellowship was to remove the sin that was committed, and the only way to do that was through a blood sacrifice. When a person repented and made a proper offering through the priest, his sacrifice was meant to show the genuineness of his penitence by obedience to God’s requirement. God accepted that faithful act and granted forgiveness.