ABIATHAR (Hebrew 'Ebhithār 'father of abundance'). - High priest, great-grandson of Eli through Phinehas, son of the high priest Ahimelech; he escaped the massacre that Saul made of his father, of the priests and of the inhabitants of Nob for having sheltered David, who was persecuted by the king, and he took refuge at Mizpah (Moab) with David. He then remained faithful at David's side in his wanderings, and with the ephod that he had brought with him he made known to him the divine will (I Sam. 23:6-13). He was present at and directed, together with Zadok, the solemn transfer of the ark to Jerusalem (I Chron. 15:11 ff.).
The simultaneity of two high priests constitutes a singular problem. When David, during Absalom's insurrection, had to abandon the capital, A. remained there with Zadok and supplied the king with valuable information (II Sam. 15:24-29, 35-37; 17:15). In the last years of David's life he supported Adonijah in his attempt to usurp the throne (I Kings 1:7, 19); but Solomon, having succeeded David, was generous with the traitor and limited himself, in remembrance of the services rendered to his father, to confining him (I Kings 2:26 f.).
In Mk. 2:26 the episode of the showbread eaten by David is referred to the time of A. rather than of Ahimelech (v.), either through a copyist's error, or because A. bore two names, or because the name of A. dominates the whole of David's time.