Translation
And it is even more superabundantly evident before [all] if another priest arises according to the likeness of MELCHIZEDEK,
Paraphrase
This is more clear, overabundantly clear to all, if another priest arises who, in several key ways, resembles MY KING IS RIGHTEOUS,
A Change in the Priesthood Had Definitely Occurred
Not only was Melchizedek not from the tribe of Levi, he was not from any of the tribes of Israel, for he lived before the man named Israel was born. He also lived long after the man called Israel had died. He was a mysterious figure who was said to have no beginning and no end. In this and other ways, he was a picture of Jesus. The point of verse 15 is that a change in the priesthood has occurred because this new High Priest, Jesus, did not come from the tribe of Levi but rather He came in a physical sense from the tribe of Judah and in a spiritual sense from that mysterious and awe-inspiring character, Melchizedek.