David put a third of the troops under Joab’s command, another third under Joab’s brother Abishai (Zeruiah’s son), and the last third under Ittai from Gath. “I am going ⌞into battle⌟ with you,” the king said to the troops.
David then told Abishai, “Sheba, son of Bichri, will do us more harm than Absalom. Take my men and go after him, or he will find some fortified cities and take the best ones for himself.”
But Abishai, son of Zeruiah, came to help David. He attacked the Philistine and killed him. Then David’s men swore an oath, saying, “You’ll never go into battle with us again. The lamp of Israel must never be extinguished.”
and said, “It’s unthinkable that I would do this, God. Should I drink the blood of these men who risked their lives? They had to risk their lives to get this water.” So he refused to drink it. These are the things which the three fighting men did.
David asked Ahimelech the Hittite and Abishai, who was Zeruiah’s son and Joab’s brother, “Who will go with me to Saul in the camp?” Abishai answered, “I’ll go with you.”