Hebrews 7:17-21 King James Version (KJV)
17 For he testifieth, Thou art a priest for ever after the order of Melchisedec.
18 For there is verily a disannulling of the commandment going before for the weakness and unprofitableness thereof.
19 For the law made nothing perfect, but the bringing in of a better hope did; by the which we draw nigh unto God.
20 And 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 unto him, The Lord sware and will not repent, Thou art a priest for ever after the order of Melchisedec:)