"This Melchizedek was king of Salem and priest of God Most High. He met Abraham returning from the defeat of the kings and blessed him" (Hebrews 7:1).
If there is anything that the book of Genesis is full of, it is genealogies. Therefore, it is very unusual when Melchizedek appears on the scene because he has no genealogy, thus there is no way to know his background. All kinds of speculations have been offered concerning this mysterious man.
Some have thought that he was Shem the son of Noah, still alive at this point if we take the chronology of Genesis 11 strictly. Some have thought that he was an angel, or perhaps an appearance of the Second Person of the Trinity—though the fact that he served a city as a king year after year makes such miraculous identifications unlikely.
The one thing that the author of Hebrews calls attention to, however, is that since this man has no official genealogy, he must have received his priesthood directly from God and not through inheritance. This, says the author of Hebrews, makes him a type or foreshadowing of Jesus Christ (Hebrews 7:1–3).
Hebrews spotlights the fact that Melchizedek’s city was Salem, later the site of Jerusalem (which would explain how David knew Jerusalem was to be the capital of the land). The word Salem means “peace,” so that this man was “King of Peace.” Similarly, melchizedek means “King of Righteousness.” In these two respects, then, Melchizedek is also a type of Christ. Establishing peace with God was his priestly work and promoting righteous government was his kingly duty.
Hebrews then focuses attention on how Abraham, the father of the faithful and the model of believers, related to Melchizedek (Hebrews 7:4–10). First of all, Abraham allowed Melchizedek to bless him, submitting to his priestly authority. The sign of this blessing was the bread and wine that Melchizedek bestowed on Abraham. Second of all, Abraham paid Melchizedek a tithe, indicating his submission.
The point being made in Hebrews to the Jews is this: the Mosaic priesthood and the Davidic kingship both descended from Abraham, and thus both were inferior to that of Melchizedek. Now that the Greater Melchizedek had come, the lesser Aaronic and Davidic forms could pass away.
Abraham immediately paid a tithe to Melchizedek, a mere shadow of the true king of righteousness, Jesus Christ. The greater Melchizedek has come. Be certain that you are found faithful.
