Hebrews contributes significantly to the doctrine that Jesus is our unique and incomparable High Priest. Thus far, the author has argued for the vast superiority of Jesus over the angels and over Moses. Now he shows why Jesus is superior to Aaron the first high priest. He continues his previous argument that Jesus is the very best of high priests.

Aaron, Moses' brother, was chosen by God from among his people to be the first high priest (Exodus 28:1-2; Leviticus 8). The people looked to the high priest to ″represent [them] in matters related to God, to offer gifts and sacrifices for sins″ (Hebrews 5:1). The high priest stood between his God and his people, not on his own merits, but on the basis of the blood that was sacrificed in atonement of sins. Like Aaron, Jesus too was called by God to the office of high priest (v. 4).

The high priest could not just walk confidently into God's presence, for he himself was a sinner (″he himself is subject to weakness″, Hebrews 5:2). Thus, he had to offer sacrifices not only for the sins of the people, but for his own (v. 3; see Leviticus 16:6). He was allowed to enter the Holy of Holies, the holiest place in the tabernacle (later, the temple) and only once a year (Hebrews 9:6-7; see Leviticus 16). No one else was allowed to enter this place, where the ark of the covenant was placed. Even Aaron was only given permission to enter on the stipulated day; otherwise he would die (Leviticus 16:2). Tradition has it that the high priest's feet were tied to a rope as he entered the Holy of Holies; in case he died inside because of his sin, his body could be pulled out.

Because the high priest was also a sinner like the people he represented before God, he would be able to deal gently with ″those who are ignorant and are going astray″ (Hebrews 5:2), unless it got to his head that he was spiritually superior to his people. The author is setting the stage for further discussions that are to follow-that Jesus is our High Priest, who is superior to all the high priests who had preceded Him, and that He would also be gentle to those who are drifting away. The theme of drifting is repeated in Hebrews, urging readers to make sure they do not drift but stay with Jesus, no matter what.