(For those priests were made without an oath; but this with an oath by him that said unto him,
The Lord swore and will not change, you are a priest forever after the order of Melchizedek:
)
All Commentaries on Hebrews 7:21 Go To Hebrews 7
Hippolytus of Rome
AD 235
For also our Father, on beholding the Good One, and on being initiated with Him, preserved the mysteries respecting which silence is enjoined, and sware, as it has been written, "The Lord sware, and will not repent.".
And this oath, (Justinus) says, our Father Elohim sware when He was beside the Good One, and having sworn He did not repent (of the oath), respecting which, he says, it has been written, "The Lord sware, and will not repent."