2 Samuel 23:13-17

13Once during the harvest, when David was at the cave of Adullam, the Philistine army was camped in the valley of Rephaim. The Three (who were among the Thirty—an elite group among David’s fighting men) went down to meet him there.

14David was staying in the stronghold at the time, and a Philistine detachment had occupied the town of Bethlehem.

15David remarked longingly to his men, “Oh, how I would love some of that good water from the well by the gate in Bethlehem.”

16So the Three broke through the Philistine lines, drew some water from the well by the gate in Bethlehem, and brought it back to David. But he refused to drink it. Instead, he poured it out as an offering to the Lord.

17“The Lord forbid that I should drink this!” he exclaimed. “This water is as precious as the blood of these men who risked their lives to bring it to me.” So David did not drink it. These are examples of the exploits of the Three.