According to the law, in fact, nearly everything must be purified with blood, and without the shedding of blood there is no forgiveness.
22. And almost all things, etc. By saying almost he seems to imply that some things were otherwise purified. And doubtless they often washed themselves and other unclean things with water. But even water itself derived its power to cleanse from the sacrifices; so that the Apostle at length truly declares that without blood there was no remission.
In these verses the apostle considers the gospel under the notion of a will or testament, the new or last will and testament of Christ, and shows the necessity and efficacy of the blood of Christ to make this testament valid and effectual. I. The gospel is here considered as a testament, the new and last will and testament of our Lord and Saviour Jesus Christ.
Commenting on Hebrews 9:15-22
And almost all things are by the law purged with blood,.... All "except a few things", as the Arabic version renders it; for some things were cleansed by water, and others purged by fire, Num 31:23. Some join the word almost with the word purged, as if the sense was, that all things were purged by blood, but not perfectly, only almost; but the former sense is best.