From Baker’s Evangelical Dictionary of Biblical Theology
Jesus as Priest and High Priest.
Although the high priesthood of Jesus is often described solely in terms of his status according to the order of Melchizedek, Hebrews 2-4 devotes a great deal of attention to the matter of the high priesthood of Jesus before introducing Melchizedek in 5:6. In 2:17 the writer of Hebrews describes Jesus as the one who has come to our aid as our high priest by making "atonement for the sins of the people." The emphasis is on the fact that, because he himself suffered the same sorts of temptations that we face, he is a "merciful and faithful" high priest (2:17-18) and, as such, he is "the apostle and high priest whom we confess" (3:1). After a lengthy digression about the faithfulness of Jesus and the importance of a corresponding faithful commitment to him on our part (3:7-4:13), the writer returns to the same issue and exhorts us to "hold firmly" to our sympathetic high priest (4:14-16) because it is in him that "we may receive mercy and find grace to help us in our time of need" (4:16). This argument regarding the gentle and sympathetic nature of our high priestly mediator continues into 5:1-10. Old Testament high priests could sympathize with the people for whom they mediated because they had to offer sacrifices for their own sins before they could offer for the people (5:2-3; 7:27; and cf. Lev 16:11-14 with Lev 16:15-19). Jesus as our New Testament high priest is sympathetic because, even though he was the son of God, he suffered agony in the face of death (Heb 5:7-8). This is where Melchizedek comes into the picture.
The first occurrence of the term "priest" in the Old Testament is in reference to the pre-Israelite "Melchizedek king of Salem … priest of God Most High" (Gen 14:18), to whom Abram paid a tithe. Melchizedek reappears in Psalm 110:4, referring to the royal Davidic "priest forever, in the order of Melchizedek" (v. 4). This, in turn, became the pattern for the thematic development of the Melchizedekian priesthood of Jesus Christ in Hebrews 5-7 since, not being a descendant of Aaron, he could not be a priest according to the order of Aaron (Heb 7:11-14). Nevertheless, just as Aaron was divinely appointed to this office so was Jesus (vv. 4-5), but the high priesthood of Jesus was "in the order of Melchizedek" (vv. 6, 9-10). This makes the high priesthood of Jesus distinct and superior from that of Aaron and his successors on several counts.
First, Jesus "has become a high priest forever" (6:20). Aaronic priests died and therefore had only a temporary priesthood (7:23). But Jesus abides forever as a priest according to the order of Melchizedek and therefore has a permanent priesthood through which he can save us completely and eternally (7:24-25).
Second, since the Old Testament levitical priests paid a tithe to Melchizedek while they were still in the loins of Abraham, their order of priesthood is inferior to the order of Melchizedek (7:4-10).
Third, if the Aaronic priesthood had brought perfection there would have been no need for another priest to arise according to another order (i.e., the order of Melchizedek, 7:11). Moreover, in this connection, there was a necessary and corresponding shift from the old and obsolete covenant mediated by the old priesthood (i.e., the Mosaic covenant with its relatively weak and useless law, 7:11, 18-19; 8:13) to a new and better covenant mediated by the better priesthood (i.e., the New Covenant with its better promises, 7:22; 8:1-13). Direct references to Melchizedek and to Jesus as a priest according to the order of Melchizedek as opposed to the order of Aaron are limited to Hebrews 5-7.
Therefore, just as the discussion of the high priesthood of Jesus in the Book of Hebrews begins without direct reference to Melchizedek (see above), so it ends without it. In fact, the references to the (high) priesthood of Christ in Hebrews 9:7-11 and 9:24-10:25 focus more on the offering of his own blood as a sacrifice than on his priestly office. However, in Hebrews 10:13 the writer once again alludes to Psalm 110:1 when he refers to Jesus as the priest who has offered himself up as our sacrifice and since that time "waits for his enemies to be made his footstool." This is, of course, a royal motif. This suggests that Jesus, like Melchizedek, is a king who is also a priest. In fact, in some sense David, who is likely to have been the initial referent in Psalm 110, also legitimately exercized priestly prerogatives on some occasions (see esp. 2 Sam. 6). According to some scholars, even if David wrote Psalm 110 (as the title of the psalm seems to suggest), still "my lord" in verse 1 may be a formulaic way of saying "me" (thus yielding the translation, "The Lord says to me" but see Matt 22:41-46).
The Priesthood of Believers.
This (royal) high priesthood of Jesus Christ connects to the "royal priesthood" of believers: "you are … a royal priesthood, a holy nation" (1 Peter 2:9a). The obvious reference to Exodus 19:6 suggests that the church functions in this present age as God's New Testament kingdom of priests much like the nation of Israel did in the Old Testament. As such we are responsible to carry out the ministry of proclaiming to the world "the praises of him who called you out of darkness into his wonderful light" (1 Peter 2:9b).
A closely related idea (but without the "royal" connections) is Peter's earlier description of the church as a group of believers who are being (NIV), or should allow themselves to be (NRSV), "built into a spiritual house [Jesus himself being the living and choice cornerstone, 1 Peter 2:4, 6-8] to be a holy priesthood, offering spiritual sacrifices acceptable to God through Jesus Christ" (1 Peter 2:5). Thus, as fellow priests with Jesus we offer up to God our sacrifices of praise (Heb 13:15), our doing good and sharing (Heb 13:16), and ultimately our present physical bodies in the interest of conforming to his standards (Rom 12:1-2). It is important to observe that here the corporate priesthood of the church shades into the priesthood of the individual believer.
Moreover, our ministry in the gospel can be described as an offering of our very life in priestly service to the church (Php 2:17), by which we can produce a harvest of sanctified people whom we present to God as an acceptable offering. Finally, corporate Israel in the Old Testament functioned as a kingdom of priests in both its mediation between God and the other nations and in its service of worship to the Lord in the sanctuary (Exod 19:5-6). Similarly, the priesthood of the church has mediatorial features as well as aspects that correspond to the sanctuary worship of the Old Testament, sometimes expressed separately and sometimes jointly in the various New Testament passages related to the
priesthood of believers.
Richard E. Averbeck