Three of the thirty chief men went down to the rock to David, into the cave of Adullam; and the host of the Philistines were encamped in the valley of Rephaim.
And so he poured the water out on the ground because he just felt unworthy to drink that water. He felt that those guys that were willing to hazard their lives for a thing like that better that they give it to the Lord. So he poured it out to the Lord, verse eighteen.