2 Samuel 23:13-17

And three of the thirty chief men went down, and came to David in the harvest time unto the cave of Adullam; and the troop of the Philistines was encamped in the valley of Rephaim. And David was then in the stronghold; and the garrison of the Philistines was then in Beth-lehem. And David longed, and said, Oh that one would give me water to drink of the well of Beth-lehem, which is by the gate! And the three mighty men brake through the host of the Philistines, and drew water out of the well of Beth-lehem, that was by the gate, and took it, and brought it to David: but he would not drink thereof, but poured it out unto Jehovah. And he said, Be it far from me, O Jehovah, that I should do this: shall I drink the blood of the men that went in jeopardy of their lives? therefore he would not drink it. These things did the three mighty men.