2 Samuel 3:6

Abner made himself strong for the house of Saul. The Hebrew really means that until this miserable quarrel about Rizpah, Abner had been the mainstay of Ishbosheth's throne and dynasty. She is proved to have been a noble woman, with a warm and devoted heart, by the narrative in 2 Samuel 21:8-11 . But the harem of a deceased king was looked upon as the special inheritance of his successor; and Absalom, by taking David's concubines ( 2 Samuel 16:21 , 2 Samuel 16:22 ), treated his father as a dead man, and committed so overt an act of treason as made reconciliation impossible. So Solomon put his brother Adonijah to death for asking Abishag to wife ( 1 Kings 2:23-25 ). Still, as Bathsheba there saw no impropriety in Adonijah's request, and as Solomon deposed Abiathar and put Joab to death for complicity, as we must conclude, in Adonijah's request, it was probably part of some scheme of conspiracy, and that, if granted, it would have been used by Adonijah as a proof that the kingdom really was his. Here there was no plot, and as Rizpah had probably always lived apart from Ishbosheth, Abner may have expected that the king would see no difficulty in the matter.