Hyssop. — The mention of this connects this verse with the priestly ordinances concerning leprosy and contact with a dead body (Leviticus 14; Numbers 19); but generally it is a repetition of the former prayer to have the breach made in the covenant - relationship healed. (Comp. Isaiah 1:18.)
Related Commentaries of Psalms 51:7
Psalms 51:7
7 Purge me with hyssop, and I shall be clean: wash me, and I shall be whiter than snow.