1 Chronicles 11:15-20 NIV

15 Three of the thirty chiefs came down to David to the rock at the cave of Adullam, while a band of Philistines was encamped in the Valley1 of Rephaim.

References for 1 Chronicles 11:15

16 At that time David was in the stronghold,2 and the Philistine garrison was at Bethlehem.

References for 1 Chronicles 11:16

17 David longed for water and said, "Oh, that someone would get me a drink of water from the well near the gate of Bethlehem!"
18 So the Three broke through the Philistine lines, drew water from the well near the gate of Bethlehem and carried it back to David. But he refused to drink it; instead, he poured3 it out before the LORD.

References for 1 Chronicles 11:18

19 "God forbid that I should do this!" he said. "Should I drink the blood of these men who went at the risk of their lives?" Because they risked their lives to bring it back, David would not drink it. Such were the exploits of the three mighty men.
20 Abishai4 the brother of Joab was chief of the Three. He raised his spear against three hundred men, whom he killed, and so he became as famous as the Three.

References for 1 Chronicles 11:20