Hebrews 7:21
(for they are become priests without the swearing of an oath, but he with the swearing of an oath, by him who said, as to him, The Lord has sworn, and will not repent of it, Thou art priest for ever according to the order of Melchisedec;)
Psalm 110:4
Jehovah hath sworn, and will not repent, Thou art priest for ever after the order of Melchisedek.
Hebrews 7:17
For it is borne witness, Thou art a priest for ever according to the order of Melchisedec.
1 Samuel 15:29
And also the Hope of Israel will not lie nor repent; for he is not a man, that he should repent.
Hebrews 6:16-18
For men indeed swear by a greater, and with them the oath is a term to all dispute, as making matters sure.