King David grew old and sickly and suffered from chills that couldn’t be warmed by merely piling on blankets. His physicians prescribed a treatment that to us sounds strange, but was an accepted medical practice at the time.
The doctors said to find a young virgin to care for the king and to lie in bed with him to keep him warm. The belief at the time was that the vitality and warmth of the youth would pass on to the elderly.
1 Kings 1:3 says that they searched throughout all the territory of Israel to find the right woman.
The beautiful Abishag the Shunammite was chosen for the job. Though she was hired on as a nurse, because of the intimate manner of her service, she was also considered a wife or concubine.
She cared for David until his death. After his death, she got caught in a political power play. Adonijah, the son of David and Haggith, presumed himself to take over David’s reign. Instead, God appointed Solomon. So Adonijah came to Bathsheba, accepting defeat, but asking her if she would talk to Solomon and let Adonijah take Abishag as wife.
Though he presented it as a case of love, love had nothing to do with it. Marrying the wife of a deceased king was a political move to obtain the crown. It would be an act of treason against the current king.
Solomon instantly recognized Adonijah’s motive and took action accordingly. He had Adonijah killed so he no longer posed a threat.
And Abishag lived the remainder of her days in the royal residence with David’s other wives.