Mormon Doctrine, pg. 92; “But under certain circumstances there are some serious sins for which the cleansing of Christ does not operate, and the law of God is that men must then have their own blood shed to atone for their sins. Murder, for instance, is one of these sins; hence we find the Lord commanding capital punishment. Thus, also, if a person has so progressed in righteousness that his calling and election has been made sure, if he has come to that position where he knows “by revelation and the spirit of prophecy, through the power of the Holy Priesthood” that he is sealed up unto eternal life (D. & C. 131:5), then if he gains forgiveness for certain grievous sins, he must “be destroyed in the flesh,” and “delivered unto the buffetings of Satan unto the day of redemption, saith the Lord God.” (D. & C. 132:19-27.)”
Hebrews 10:14; “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?”
As mentioned before, the Mormon Church teaches that King David didn’t receive a full salvation but Moses, Paul and Joseph Smith did.