What does Hebrews 9:22 mean?

Under the old covenant, sacrificial blood was required to sanctify almost everything. Forgiveness for sins, in particular, was dependent on the death of an animal. Up to this point, the writer of Hebrews has been pointing out that the old covenant was always intended, by God, as a symbol of the new covenant. The physical rituals and artifacts of the temple were given by God specifically to point towards the ministry of Jesus Christ. In many cases, those components of the old covenant were meant to be seen as limited specifically as proof that God intended to provide a more permanent solution.

Immediately prior to this verse, the writer has pointed out that even at the very beginning of the covenant between God and Israel, blood was shed in order to establish that arrangement.

Here, the writer makes it clear that the blood which was spilled in both the old and new covenants is necessary—forgiveness from sin is not possible without it. Under the old covenant, this meant repeated offerings of animal sacrifices (Hebrews 7:27). In the new covenant, this means a single, perfect, once-for-all shedding of blood by Christ. Upcoming verses will focus on how this sacrifice by Jesus fulfills the symbolism of the old covenant and resolves the weaknesses of the temple rituals.