In the trumpet series there was a break between the first four trumpets (8:7-12) and the last three (signaled by a flying eagle announcing three more "woes," 8:13). In the bowl series, as in the seven judgments of chapter 14, the break is between the first three and the last four, signaled by a solemn exchange between the angel of the waters (16:5-6) and the altar (v. 7).
The first three bowls parallel the first three trumpets (8:7-12) in that they affect (in sequence) the earth, the sea and the fresh waters. Yet the bowls do not merely repeat the earlier series. The differences are as conspicuous as the similarities. First, the intensity is greater. The trumpet series affected one-third of the earth, sea and fresh water respectively (as well as a third of the sun, moon and stars), while the judgments introduced by the bowls have no such limitation. Second, in contrast to the earlier series, humans are affected from the start. A third, more important difference is that the bowl series presupposes the conflict in the intervening chapters between the Christian community and the beast. The humans who suffer from these plagues are specifically those who had the mark of the beast and worshiped his image (v. 2). Still another difference, reflected perhaps in the fact that all seven judgments are repeatedly called "plagues" (15:1, 8; 16:9; compare 9:18), is that they correspond more closely to the Exodus plagues than do the judgments introduced in the trumpet series.
The first bowl brings ugly and painful sores on those who bear the beast's mark (v. 2; see Ex 9:8-12); the second turns the sea into blood like that of a dead man, and every living thing in the sea died (v. 3), while the third turns the fresh waters to blood (v. 4; see Ex 7:14-25). In the trumpet series there were no ugly sores or boils; a third of the sea was turned to blood, but as only one detail among several (8:8-9); fresh waters were poisoned but not turned to blood (8:10-11). Here, the angel in charge of the waters comments on the judgment of the fresh waters introduced by the third bowl (vv. 5-6), and with a response from the altar (v. 7) provides a chorus to the first three bowls and a momentary pause in the action. The pattern of a pronouncement followed by a response introduced by yes recalls the earlier exchange between a "voice from heaven" and "the Spirit" about "the dead who die in the Lord" (14:13), also following a series of three angels and preceding the appearance of four more.
Taken together, the angel's pronouncement and the altar's response form a kind of hymn that begins and ends with an acknowledgment of the justice of God's wrath displayed on the earth: You are just in these judgments, you who are and who were, the Holy One, because you have so judged (v. 5), and Yes, Lord God Almighty, true and just are your judgments (v. 7). Like "the song of Moses . . . and the song of the Lamb" (15:3), the angel's hymn addresses the Lord God Almighty (v. 7) and echoes such lines from the previous song as "just and true are your ways" (15:3), "for you alone are holy," and "your righteous acts have been revealed" (15:4).
The heart of the judgment hymn is the ironic pronouncement in verse 6: for they have shed the blood of your saints and prophets, and you have given them blood to drink as they deserve. The sentiments are similar to those expressed in the Jewish apocryphal work Wisdom of Solomon, reflecting on how the plagues were appropriate to the Egyptians' sins: "In return for their foolish and wicked thoughts, which led them astray to worship irrational serpents and worthless animals, you sent upon them a multitude of irrational creatures to punish them, so that they might learn that one is punished by the very things by which one sins" (Wis 11:15 NRSV). Wisdom of Solomon makes no mention of the plague that turned the waters of the Nile to blood (Ex 7:14-25), but in Revelation the same principle applies: those who shed the blood of martyrs are themselves punished with a plague of blood.