Are you a Mormon? perhaps a skeptic Bible detractor? The phrase you refer to, misquote and yank completely out of context to gloat about simply means that God gave David everything pertaining to Saul, even the kingdom. John Gill comments as follows at 2 Sam. 12:8: "...though we read of no more than one [wife] that belonged to Saul, if he is meant by his master, excepting Rizpah his concubine, nor ever of David taking them into his bosom and bed; wherefore this can be understood only of his having them at his disposal, to give them to whom he pleased; the word may be rendered his "women", as well as his "wives", and may design his daughters, Merab and Michal, who were both given to David, though taken again and given to others..." There is no verse indicating that David ever lay with Saul's wives, and this verse is not a contradiction or abrogation of God's law at Dt. 17:17.