Psalm 51:7
Cleanse me with hyssop, and I will be clean; wash me, and I will be whiter than snow.
King David knew hyssop was used by the priests to dip into the blood of sacrificial animals. With it, they would sprinkle blood onto the sinner, thus making them clean of their sins.
Here, David asks God to cleanse him with hyssop, just as the priests cleansed others. He knew if God cleansed him, then his sins would be gone without a trace.
Even Isaiah prophesied of sins as red as scarlet becoming as white as snow. If God cleanses the sinner, then who can make them unclean again? If God Himself sprinkles His own blood, how much better is His sacrifice than the blood of animals? King David had sinned grievously in taking Bathsheba, the wife of Uriah, for himself.
Psalm 51 is his repentance unto God. He knew if God didn’t cleanse him, nothing could. The Lord, in His mercy, heard his cries and granted his tear-soaked prayer.
