There are two references in the Bible to people who bear that name:
- A daughter of Ahimaaz, who became a wife of Saul and the mother of his four sons and two daughters, one of whom is Michal, David's first wife.
- A woman from Jezreel, who became David's second wife, after he fled from Saul, leaving Michal, his first-ever wife, behind, and the mother of Amnon, David's first-born.
Some scholars suggest that the two may be, in fact, one person. In 2 Samuel 12:8, God tells David through the prophet Nathan, "I gave your master's house to you, and your master's wives into your arms." Jon Levenson suggests that this implies David took Ahinoam from Saul. Levenson goes on to note that Ahinoam is always mentioned before Abigail and that she bears David a son before Abigail does, and concludes from this that "she was already married to David when the conflict with Nabal erupted." However, with Jonathan about the same age as, if not older than, David, Ahinoam, the wife of Saul, would be too old to give birth to David's first-born son, Amnon. Another objection is that the marriage of Ahinoam and David occurred during The Civil War between the House of David and the House of Saul. Nevertheless, when David had run away from Saul and dwelt with Achish, king of Gath, he had his two wives Ahinoam and Abigail with him as per 1 Samuel 27:3.
The term "your master's wives" would actually imply that David inherited Saul's harems, as was common among ancient kings.
Adherents of source criticism suggest that references to a woman called Ahinoam being Saul's wife belong to the account of the republican source of the Books of Samuel, while in the passages ascribed to the monarchial source, the only mention of a woman called Ahinoam is the description of her as a wife of David.
Since Ahinoam's name usually precedes that of Abigail, it has been suggested that David married Ahinoam before he married Abigail. However, if her son Amnon was David's firstborn son, then the order of their names might indicate Ahinoam's status as the crown prince's mother. Ahinoam is with David during his stay with King Achish of Gath, and is taken captive when Amalekites raid Ziklag, David's Philistine base. She is among those who go with David to Hebron when he becomes king over Judah (2 Sam 2:2).
Additionally, Leviticus 20:14 forbids men from marrying their mothers-in-law, and Ahinoam, wife of Saul, was the mother of David's first wife Michal, whom David considered to legally be his wife even after fleeing, and David was never indicted by any prophets for his marriage to Ahinoam.