Kitto's Popular Cyclopedia of Biblial Literature
Ab´ishag (father of error), a beautiful young woman of Shunam, in the tribe of Issachar, who was chosen by the servants of David to be introduced into the royal harem, for the special purpose of ministering to him, and cherishing him in his old age. She became his wife; but the marriage was never consummated. Some time after the death of David, Adonijah, his eldest son, persuaded Bathsheba, the mother of Solomon, to entreat the king that Abishag might be given to him in marriage. But as rights and privileges peculiarly regal were associated with the control and possession of the harem of the deceased kings, Solomon detected in this application a fresh aspiration to the throne, which he visited with death (1 Kings 1:1-4; 1 Kings 2:13-25) [ADONIJAH].
Kitto, John, ed. Entry for 'Abishag'. "Kitto's Popular Cyclopedia of Biblial Literature". https://www.studylight.org/encyclopedias/eng/kbe/a/abishag.html.