Hebrews 7:20-24

20And inasmuch as not without an oath he was made priest : 21(For those priests were made without an oath; but this with an oath by him that said to him, The Lord swore and will not repent, Thou art a priest for ever after the order of Melchizedek:)1 22By so much was Jesus made a surety of a better testament. 23And they truly were many priests, because they were not allowed to continue by reason of death: 24But this man, because he continueth ever, hath an unchangeable priesthood.2