Hebrews 5:6

also said in another passage, You are a priest forever in the order of Melchizedek.

For it has been testified:

You are a priest forever
in the order of Melchizedek.

The Lord has sworn an oath and will not take it back:
“Forever, You are a priest
like Melchizedek.”

but He became a priest with an oath made by the One who said to Him:

The Lord has sworn,
and He will not change His mind,
You are a priest forever.

and He was declared by God a high priest in the order of Melchizedek.

Jesus has entered there on our behalf as a forerunner, because He has become a high priest forever in the order of Melchizedek.

Then Melchizedek, king of Salem, brought out bread and wine; he was a priest to God Most High.

without father, mother, or genealogy,
having neither beginning of days nor end of life,
but resembling the Son of God—

remains a priest forever.

And this becomes clearer if another priest like Melchizedek appears,

Treasury of Scripture Knowledge

As he saith also in another place, Thou art a priest for ever after the order of Melchisedec.

and He was declared by God a high priest in the order of Melchizedek.

Jesus has entered there on our behalf as a forerunner, because He has become a high priest forever in the order of Melchizedek.

without father, mother, or genealogy,
having neither beginning of days nor end of life,
but resembling the Son of God—

remains a priest forever.

The Lord has sworn an oath and will not take it back:
“Forever, You are a priest
like Melchizedek.”

Then Melchizedek, king of Salem,

brought out bread and wine; he was a priest to God Most High.

and He was declared by God a high priest in the order of Melchizedek.

For it has been testified:

You are a priest forever
in the order of Melchizedek.