Hebrews 7:21

Hebrews 7:21 AMP

(for those Levites who formerly became priests [received their office] without [its being confirmed by the taking of] an oath, but this One [was designated] with an oath through the One who said to Him, “THE LORD HAS SWORN AND WILL NOT CHANGE HIS MIND or REGRET IT, ‘YOU (Christ) ARE A PRIEST FOREVER’ ”).
AMP: Amplified Bible