because by a single offering He has made perfect for all time those who are being sanctified.
Here the apostle raises up and exalts the Lord Jesus Christ, as high as he had laid the Levitical priesthood low. He recommends Christ to them as the true high priest, the true atoning sacrifice, the antitype of all the rest: and this he illustrates, I. From the purpose and promise of God concerning Christ, which are frequently recorded in the volume of the book of God, Heb 10:7.
Commenting on Hebrews 10:7-18
For by one offering,.... The same as before; himself, body and soul; this is a reason why he is set down, and will continue so for ever, and why he expects his enemies to be made his footstool; because by one sacrifice for sin, which he has once offered, he hath perfected for ever them that are sanctified; that is, who are sanctified by God...
Verse 14. For by one offering. By offering himself once on the cross. The Jewish priest offered his sacrifices often, and still they did not avail to put away sin; the Saviour made one sacrifice, and it was sufficient for the sins of the world. He hath perfected for ever, He hath laid the foundation of the eternal perfection.