Jesus and the Melchizedek Priesthood
A point Christians and Mormons agree on is that Melchizedek and Jesus were in the Melchizedek priesthood. The point of contention is whether or not they were the only ones holding that priesthood. Christians say yes, Mormonism says no. In this post, I will expand on why Christians state that and the importance they have for stating that.
To do that we have to look at the book of Hebrews, because it is the only place that gives us any details about the Melchizedek priesthood. In 7:22-28 it contrasts Christ’s priesthood with the Aaronic priesthood.
“22] By so much was Jesus made a surety of a better testament.
 And they truly were many priests, because they were not suffered to continue by reason of death:
 But this man, because he continueth ever, hath an unchangeable priesthood.
 Wherefore he is able also to save them to the uttermost that come unto God by him, seeing he ever liveth to make intercession for them.
 For such an high priest became us, who is holy, harmless, undefiled, separate from sinners, and made higher than the heavens;
 Who needeth not daily, as those high priests, to offer up sacrifice, first for his own sins, and then for the people’s: for this he did once, when he offered up himself.
 For the law maketh men high priests which have infirmity; but the word of the oath, which was since the law, maketh the Son, who is consecrated for evermore.
Note the contrasts. In the Aaronic priesthood there were many priests (v. 23, 28) because they died and could not continue in the priesthood. In striking contrast to “men” in verse 28 is the “Son”. Not other men. And there is no need for others because Jesus “is consecrated for evermore.” This is a contrast that continues throughout the book. The contrast is always between the many priests of the Aaronic priesthood and the one priest of the Melchizedek priesthood. There are no “priests” when it comes to the Melchizedek priesthood.
Secondly, note the contrast in verse 27. They daily sacrificed. He once for all. Again this is expanded on greatly in the coming chapters. For example, Hebrews 10:
10] By the which will we are sanctified through the offering of the body of Jesus Christ once for all.
 And every priest standeth daily ministering and offering oftentimes the same sacrifices, which can never take away sins:
 But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God;
 From henceforth expecting till his enemies be made his footstool.
 For by one offering he hath perfected for ever them that are sanctified.
What a striking contrast. Aaronic priests stand working because their work of sacrificing is never done. Jesus sits because his work of sacrificing is done.
The Bible does not talk about subsequent priests in the Melchizedek priesthood – in fact, the idea of subsequent priests violates the whole argument put forth in the book of Hebrews. There are no successors because Jesus remains forever our priest – because Jesus has made the one offering “once for all”.
The Bible intertwines the Melchizedek priesthood with Jesus’ sacrifice for sin. That is what Christians immediately think of when they hear the phrase, “Melchizedek priesthood”. They immediately think of God’s great love for them in sending Jesus to do everything for them so that they are perfect forever, not by anything they do, but by his one offering.