Hebrews 10:2

for then, would they not have ceased to be offered? because the worshipers, after being once cleansed, would no longer have a consciousness of sins.

Hebrews 9:13-14

For if the blood of bulls and goats, and the ashes of a heifer sprinkling the unclean, cleanses them as it respects the purity of the flesh,

Hebrews 10:17

he adds, And their sins and iniquities I will remember no more.

Treasury of Scripture Knowledge

Summary

For then would they not have ceased to be offered? because that the worshippers once purged should have had no more conscience of sins.

General references

Bible References

Once

Hebrews 10:17
he adds, And their sins and iniquities I will remember no more.
Hebrews 9:13
For if the blood of bulls and goats, and the ashes of a heifer sprinkling the unclean, cleanses them as it respects the purity of the flesh,

General references

Hebrews 10:18
Now, where remission of these is, there is no more offering for sin.