Hebrews 7:3, 15, 17, 21

This Melchizedek has no father or mother, and no record of any of his ancestors. He was never born and he never died, but his life is like a picture of the Son of God, a King-Priest forever!

And all this is made even clearer if there was another King-Priest raised up with the rank of Melchizedek.

For it says in the Psalms, You are like Melchizedek, a King-Priest forever!

but with Jesus, God affirmed his royal-priesthood with his promise, saying, The Lord has made a solemn oath and will never change his mind, “You are a King-Priest forever!”