It is possible that the dog’s head is a reference to David,1 though it is more likely that it is meant to emphasize the offence Abner had taken at Ish-bosheth’s accusation. In the ancient Near East, dogs were not typically known as pets but as wild creatures which roamed the streets in packs scavenging for food scraps to eat. As a result, dog
became a word of reproach (see 1 Samuel 17:43; 1 Samuel 24:14; 2 Samuel 9:8; 2 Samuel 16:9; Psalm 22:20; Proverbs 26:11; Isaiah 56:10–11).
8 Then Abner was very angry over the words of Ish-bosheth and said, “Am I a dog’s head of Judah? To this day I keep showing steadfast love to the house of Saul your father, to his brothers, and to his friends, and have not given you into the hand of David. And yet you charge me today with a fault concerning a woman.