So also Christ did not glorify Himself to become High Priest, but it was He who said to Him:
"You are My Son, today I have begotten You." As He also says in another place:
"You are a priest forever according to the order of Melchizedek"; who,
in the days of His flesh, when He had offered up prayers and supplications, with vehement cries and tears to Him who was able to save Him from death, and was heard because of His godly fear,
though He was a Son, yet He learned obedience by the things which He
suffered. And having been perfected, He became the author of eternal salvation to all who obey
Him, called by God as High Priest "according to the order of Melchizedek,"
of whom we have much to say, and hard to explain, since you have become dull of hearing.
Hebrews 5:5-11
(NKJV)