John Calvin Commentary Hebrews 5:10

"named of God a high priest after the order of Melchizedek." — Hebrews 5:10 (ASV)

Called of God, or named by God, etc. Since it was necessary for him to elaborate further on the comparison between Christ and Melchizedek (which he had briefly touched upon), and for the minds of the Jews to be stirred to greater attention, he therefore digresses, yet in such a way that he still continues to develop his argument.