Hebrews 7:26-28
7:26 For it is indeed fitting for us to have such a high priest: holy, innocent, undefiled, separate from sinners, and exalted above the heavens.
7:27 He has no need to do every day what those priests do, to offer sacrifices first for their own sins and then for the sins of the people, since he did this in offering himself once for all.
7:28 For the law appoints as high priests men subject to weakness, 1 but the word of solemn affirmation that came after the law appoints a son made perfect forever.
1 sn See Heb 5:2 where this concept was introduced.