Psalm 51 is David's prayer after the murder of Uriah and the adultery with Bathsheba — two of the most serious moral violations in the Old Testament. What distinguishes this psalm is its specificity: "Against thee, thee only, have I sinned" (v.4), "the bones which thou hast broken" (v.8), "restore unto me the joy of thy salvation" (v.12). Moral injury damages the deep structure of the self — the Hebrew word for "broken" — shavar — is the word for shattering, not bending. David is describing something at the structural level that requires more than ordinary forgiveness.
Hebrews 9:14 speaks to the conscience directly: "How much more shall the blood of Christ, who through the eternal Spirit offered himself without spot to God, purge your conscience from dead works to serve the living God?" The Greek word katharizō — "purge" — means to cleanse, to purify completely. The specific target is the conscience — not just the behavior record, but the internal organ of moral judgment that has been damaged. Christ's work is described as reaching that specific place.
Commentary is from a charismatic Protestant perspective, drawing on KJV text and public-domain sources including Spurgeon, Andrew Murray, and Matthew Henry.