Hebrews 7:1

Paul wishing to show the difference between the New and Old Covenant, scatters it everywhere; and shoots from afar, and noises it abroad, and prepares beforehand. For at once even from the introduction, he laid down this saying, that "to them indeed He spake by prophets, but to us by the Son," and to them "at sundry times and in divers manners," but to us through the Son. Afterwards, having discoursed concerning the Son, who He was and what He had wrought, and given an exhortation to obey Him, lest we should suffer the same things as the Jews; and having said that He is "High Priest after the order of Melchisedec," and having oftentimes wished to enter into the subject of this difference, and having used much preparatory management; and having rebuked them as weak, and again soothed and restored them to confidence; then at last he introduces the discussion on the difference of the two dispensations to ears in their full vigor. For he who is depressed in spirits would not be a ready hearer. And that you may understand this, hear the Scripture saying, "They hearkened not to Moses for anguish of spirit." Therefore having first cleared away their despondency by many considerations, some fearful, some more gentle, he then from this point enters upon the discussion of the difference of the dispensations. And what does he say? "For this Melchisedec, King of Salem, Priest of the Most High God." And, what is especially noteworthy, he shows the difference to be great by the Type itself. For as I said, he continually confirms the truth from the Type, from things past, on account of the weakness of the hearers. "For" (he says) "this Melchisedec, King of Salem, Priest of the Most High God, who met Abraham returning from the slaughter of the Kings, and blessed him, to whom also Abraham gave a tenth part of all." Having concisely set down the whole narrative, he looked at it mystically.

On receiving this promise Abraham moved on and stayed in another place in the same land, Hebron, near the Oak of Mamre.… But he received at the same time a public blessing from Melchizedek, who was "a priest of the Most High God." Many important things are written about Melchizedek in the epistle entitled "To the Hebrews," which the majority attribute to the apostle Paul, though many deny the attribution. Here we certainly see the first manifestation of the sacrifice which is now offered to God by Christians in the whole world, in which is fulfilled what was said in prophecy, long after this event, to Christ who was yet to come in the flesh: "you are a priest forever, after the order of Melchizedek." Not, it is observed, in the line of Aaron, for that line was to be abolished when the events prefigured by these shadows came to the light of day.