What does Revelation 16:5 mean?
The apostle John reports in this verse that he heard an angel in charge of the waters—the waters that have just become blood—extol God. The angel addresses God as, "O Holy One, " and declares that He is just and eternal.As the Holy One, God cannot think or do anything wrong or sinful. So, what He does in judging the wicked is right and in keeping with His abhorrence of evil. As the eternal God, He has always been holy and just, is holy and just now, and always will be holy and just. He never accuses the innocent and never excuses the guilty. The angel understands clearly that God is the source of the judgments. He agrees fully with God's action of turning the waters into blood. He yields his administration of the waters into God's righteous hands.
In the fifth seal judgment, the martyrs had begged God to punish their murderers (Revelation 6:9–11). Now the time of vengeance on their behalf has arrived.
Revelation 16:1–7 reports the beginning of the bowl judgments which were predicted in Revelation 15:5–8. The first and second judgments resemble the plague of boils and the plague of blood that God brought upon the Egyptians when Pharaoh refused to let the Hebrews leave Egypt (Exodus 7:19–21; 9:8–12). The third judgment turns the water sources into blood. The second and third judgments resemble the third trumpet judgment (Revelation 8:8), but their intensity is greater. A break occurs in 16:5–7 as an angel reflects on the first three bowl judgment and affirms that God is just to judge the wicked.
This chapter explains the bowl judgments, which are the last and most severe of God's outpouring of wrath on earth. The first three bowls bring sores, seas of blood, and rivers of blood. After a declaration of God's justice come the next three bowl judgments, involving scorching sunlight, darkness, and a drying of the Euphrates to clear the way for an invading army. In the final, seventh bowl judgment, an earthquake tears Jerusalem into three parts, levels cities worldwide, and displaces islands and mountains. Hundred-pound hailstones fall, but unbelievers refuse to repent and instead continue to curse God.