As he saith also in another place, Thou art a Priest for ever: the Spirit proves his call and investiture into this office, its confirmation to him for ever, by another testimony of the Father about it, penned by David, Psalms 110:4, and ratified to be so by the Lord himself, Matthew 22:41-45; that he as man was David's Son: as God-man, David's Lord, and the grand officer to atone God by his sacrifice for sinners, and to intercede for them. By this word of God to him was he invested with the most glorious priesthood, and settled in that which he must execute for ever, Hebrews 7:24, having no successor in it. After the order of Melchisedec; which order was a singular and most excellent one, such as Aaron's did but imperfectly shadow to us. It was a royal priesthood God installed him in, such as was Melchisedec s, largely described, Hebrews 7:1-28. This was by God the Father revealed to David, and prophesied by him to the church, but actually fulfilled as to proclamation and inauguration at his ascension into the holy of holiest in heaven, where he actually in the flesh doth officiate and minister in it.
Related Commentaries of Hebrews 5:6
Hebrews 5:6
6 As he saith also in another place, Thou art a priest for ever after the order of Melchisedec.