Is Jesus' priesthood after the order of Aaron or Melchizedek?
Jesus' priesthood is after the order of Melchizedek, not Aaron. Hebrews 6:20 says He was made a high priest forever after the order of Melchizedek. Hebrews 9 describes Him entering the greater, heavenly tabernacle by His own blood, obtaining eternal redemption, which fits that superior priesthood.
Les explains that Hebrews 9 presents Christ as a high priest of good things to come, ministering in a greater and more perfect tabernacle not made with hands—not an earthly building. He entered the holy place once for all by His own blood, not by the blood of goats and calves, obtaining eternal redemption. Going back to Hebrews 7:1 and 6:20, Les points out Melchizedek and says Jesus was made a high priest forever after the order of Melchizedek, not after the order of Aaron.
Whither the forerunner is for us entered, even Jesus, made an high priest for ever after the order of Melchisedec.