Carl Friedrich Keil and Franz Delitzsch Old Testament Commentary

Notwithstanding this truthful assertion of his innocence, Saul pronounced sentence of death, not only upon the high priest, but upon all the priests at Nob, and commanded his רצים, "runner," i.e., halberdiers, to put the priests to death, because, as he declared in his wrath, "their hand is with David (i.e., because they side with David), and because they knew that he fled and did not tell me." Instead of the Chethibh אזנו, it is probably more correct to read אזני, according to the Keri, although the Chethibh may be accounted for if necessary from a sudden transition from a direct to an indirect form of address: "and (as he said) had not told him." This sentence was so cruel, and so nearly bordering upon madness, that the halberdiers would not carry it out, but refused to lay hands upon "the priests of Jehovah."