Melchizedek, mentioned only twice in the entire Old Testament (Gen. 14:18; Ps. 110:4), is the focus of attention in the first part of Hebrews 7. The author of the epistle demonstrates his Biblical skills as he explains the priesthood of Christ in the order of Melchizedek.
From a modern point of view the writer’s arguments appear to be somewhat labored. He seems to be reading more into the Old Testament passages that mention Melchizedek than the passages actually say. But the original readers were Hebrews. They believed that the divinely instituted Levitical priesthood was inviolable. They knew that the priesthood of Aaron had to be perpetual, because God himself had ordained the priesthood by law.
The author of Hebrews counters the objections of readers of the Old Testament Scriptures by discussing the differences between the Aaronic priesthood and the superior order of Melchizedek. These differences consist of the absence of a genealogy for Melchizedek; the homage and tithe Abraham paid Melchizedek; and the confirmation of Melchizedek’s priesthood by divine oath centuries after the Levitical priesthood was established by law.
The evidence that shows God’s design in terminating the temporal priesthood of Aaron and inaugurating the eternal priesthood of Melchizedek is irrefutable. Jesus, to whom the author indirectly referred and who at last is mentioned by name, has become high priest in Melchizedek’s order and is a “guarantee of a better covenant” (7:22).