Apostol § 317

Brethren, on the one hand there is an annulling of the former commandment because of its weakness and unprofitableness, for the law made nothing perfect; on the other hand, there is the bringing in of a better hope, through which we draw near unto God. And inasmuch as He was not made priest without an oath (for they have become priests without an oath, but He with an oath by Him who said unto Him: “The Lord has sworn and will not change His mind, Thou art a priest for ever after the order of Melchizedek’”), by so much more Jesus has become a surety of a better testament. And there truly were many priests, because they were prevented by death from continuing in office. But He, because He continues for ever, has an unchangeable priesthood. Therefore He is also able to save to the uttermost them that come unto God through Him, since He ever lives to make intercession for them.