2 Samuel 12:13

The Lord - hath put away thy sin - Many have supposed that David' s sin was now actually pardoned, but this is perfectly erroneous; David, as an adulterer, was condemned to death by the law of God; and he had according to that law passed sentence of death upon himself. God alone, whose law that was could revoke that sentence, or dispense with its execution; therefore Nathan, who had charged the guilt home upon his conscience, is authorized to give him the assurance that he should not die a temporal death for it: The Lord hath put away thy sin; thou shalt not die. This is all that is contained in the assurance given by Nathan: Thou shalt not die that temporal death; thou shalt be preserved alive, that thou mayest have time to repent, turn to God, and find mercy. If the fifty-first Psalm, as is generally supposed, was written on this occasion, then it is evident (as the Psalm must have been written after this interview) that David had not received pardon for his sin from God at the time he composed it; for in it he confesses the crime in order to find mercy.

There is something very remarkable in the words of Nathan: The Lord also hath Put Away thy sin; thou shalt not die; gam Yehovah heebir chattathecha lo thamuth , Also Jehovah Hath Caused thy sin To Pass Over, or transferred thy sin; Thou shalt not die. God has transferred the legal punishment of this sin to the child; He shall die, Thou shalt not die; and this is the very point on which the prophet gives him the most direct information: The child that is born unto thee shall Surely die; moth yamuth , dying he shall die - he shall be in a dying state seven days, and then he shall die. So God immediately struck the child, and it was very sick.