1 Chronicles 11:15-20

15Three of the thirty chief men went down to the rock to David at the cave of Adullam, when the army of Philistines was encamped in the Valley of Rephaim.

16David was then in the stronghold, and the garrison of the Philistines was then at Bethlehem.

17And David said longingly, "Oh that someone would give me water to drink from the well of Bethlehem that is by the gate!"

18Then the three mighty men broke through the camp of the Philistines and drew water out of the well of Bethlehem that was by the gate and took it and brought it to David. But David would not drink it. He poured it out to the Lord

19and said, "Far be it from me before my God that I should do this. Shall I drink the lifeblood of these men? For at the risk of their lives they brought it." Therefore he would not drink it. These things did the three mighty men.

20Now Abishai, the brother of Joab, was chief of the thirty. And he wielded his spear against 300 men and killed them and won a name beside the three.