Every high priest is selected from among the people and is appointed to represent the people in matters related to God, to offer gifts and sacrifices for sins. He is able to deal gently with those who are ignorant and are going astray, since he himself is subject to weakness. This is why he has to offer sacrifices for his own sins, as well as for the sins of the people. And no one takes this honor on himself, but he receives it when called by God, just as Aaron was.

Hebrews 5:1-4

The discussion of Jesus, our great High Priest continues through chapter 5.  Here in these verses, we have a description of what a high priest is; someone appointed from among the people to represent them in “matters related to God.” Thus, we would say that the high priest performs the duties of an intermediary between Man and God.  In the case of the Old Testament priesthood, they would present sacrifices for sins and other offerings to God according to the Law. In making intercession, the priest is in a position to understand the plight of humanity since he has the same problems, challenges, and temptations as everyone else; he offers sacrifices for his own sins as well as for the rest of the people… and he does not appoint himself as high priest, for this is an office ordained by God.

In the same way, Christ did not take on himself the glory of becoming a high priest. But God said to him,

“You are my Son;
    today I have become your Father.”

And he says in another place,

“You are a priest forever,
    in the order of Melchizedek.”

Hebrews 5:5-6

Our author is going to some pains here to demonstrate that Jesus, as high priest, is not something that came about by any means other than the assent of God, citing two passages to indicate that His elevation to the office of high priest was indeed a divine appointment.

During the days of Jesus’ life on earth, he offered up prayers and petitions with fervent cries and tears to the one who could save him from death, and he was heard because of his reverent submission. Son though he was, he learned obedience from what he suffered and, once made perfect, he became the source of eternal salvation for all who obey him and was designated by God to be high priest in the order of Melchizedek.

Hebrews 5:7-10

This is a key passage for a couple of reasons. First, we can see three aspects of Jesus priestly ministry: First, we see Jesus’ intercessions through prayer. Throughout the Gospels, we clearly see Jesus as a man of prayer, one who is able to freely, boldly, and submissively approach the Father in prayer.  Second, we see Jesus’ priestly ministry through His obedience by the fact that He was willing to offer Himself as the ultimate and transformational sacrifice for sin, once and for all, putting to an end the need for the atoning sacrifices of the Old Covenant system.  Effectively, Jesus made the ultimate intercession with God on behalf of all humanity when He sacrificed Himself.  Third, we see the present priestly ministry of Jesus, in which He is the “source of eternal salvation for all who obey him…”  Notice the conditional nature of this sentence in “all who obey him.” Yes, Jesus is the source of eternal salvation, but we must “obey him.”  I suppose this can be taken two ways, but I take it as meaning that we obey His call to repentance, and accept the grace He has made available to all of us.

In the very last part of this passage, we see a very important fact, one that our author will explain in detail in chapter 7: Jesus, our high priest is a priest in the “order of Melchizedek.” For now, let’s just mention that this is not the order of priests who served in the Old Covenant system by the Law of Moses in the Jerusalem Temple.  This is quite significant!  That tells us that Jesus is not an Old Covenant priest at all, that He serves in an entirely different system that provides entirely different promises.  The Old Covenant system was served by priests in the order of Aaron, the Levitical priesthood.  They could not offer a sacrifice that could result in the forgiveness of sins, they offered sacrifices that could atone for sins, putting off the penalty for sin until a future date when the account would come due, so to speak.  Jesus, on the other hand took sins away completely and forever.