for then he would have had to suffer repeatedly since the foundation of the world. But as it is, he has appeared once for all at the end of the ages to put away sin by the sacrifice of himself.
26. For then must he often have suffered, etc. He shows how great an absurdity follows, if we do not count it enough that an expiation has been made by the one sacrifice of Christ. For he hence concludes that he must have died often; for death is connected with sacrifices.
In this last part of the chapter, the apostle goes on to tell us what the Holy Ghost has signified to us by the legal purifications of the patterns of the things in heaven, inferring thence the necessity of better sacrifices to consecrate the heavenly things themselves. I. The necessity of purifying the patterns of the things in heaven, Heb 9:23.
Commenting on Hebrews 9:23-28
For then must he often have suffered since the foundation of the world,.... For if it was necessary that he should often offer up himself now, which is the same as to suffer, since the sacrifice of himself, the same was necessary before; seeing sin was in the world from the beginning, and the saints from the foundation of the world had their sins expiated...