Charles Spurgeon Commentary Hebrews 7:11

"Now if there was perfection through the Levitical priesthood (for under it hath the people received the law), what further need [was there] that another priest should arise after the order of Melchizedek, and not be reckoned after the order of Aaron?" — Hebrews 7:11 (ASV)

We read in the psalm just now, You are a priest for ever after the order of Melchisedec, which proves that the priests of the order of Levi were not sufficient: there was need of a still greater priesthood.