- So also Christ did not glorify Himself so as to become a high priest, but He who said to Him, You are My Son, Today I have begotten You; just as He says also in another passage, You are a priest forever According to the order of Melchizedek. In the days of His flesh, He offered up both prayers and supplications with loud crying and tears to the One able to save Him from death, and He was heard because of His piety. Although He was a Son, He learned obedience from the things which He suffered. And having been made perfect, He became to all those who obey Him the source of eternal salvation, being designated by God as a high priest according to the order of Melchizedek. - Hebrews 5:5-10
First, like Aaron, Jesus was appointed by God to be a High Priest.
Second, like Aaron, Jesus was human.
Third, like Aaron, Jesus was sympathetic.
Fourth, like Aaron, Jesus made offerings and sacrifices. The phrase having been made perfect references Jesus’ act of offering Himself as a sacrifice. On the cross, Jesus offered Himself as the sacrifice for sin. The term perfect (teleióō) comes from the same root word translated as It is finished — teléō (cf. John 19:30). The term teleióō means to bring something to its completed end. The term also has a moral sense as it means to cleanse from sin thoroughly. Applied to Christ, it means that when Jesus completed the path of suffering and remained obedient to the Father that He was proven fit to be the Savior and High Priest of God’s people.