Revelation 16:4-7 - The Third Bowl
4 And the third angel poured out his cup on the rivers and the fountains of waters; and they became blood. 5 And I heard the angel of the waters, saying: Just art thou, who art and who wast, the Holy One, because thou hast thus judged. 6 For they have shed the blood of saints and of prophets, and thou hast given them blood to drink, and they are worthy.
7 And I heard a voice from the altar saying: Even so; Lord God Al mighty, true and just are thy judgments.