What does Revelation 9:10 mean?

John has described a demonic horde as similar to locusts, having tails and stings like scorpions, but also like horses with crowns, human faces and hair, lions' teeth, iron armor, and a roaring noise. Some interpreters compare this to the image of a stereotypical modern-day attack helicopter: a front appearing somewhat like an insect's eyes, prominent upwards-curving tail, loud noise, and with teeth painted on the front for effect. The effects of these creatures, however, seem more in line with a demonic or spiritual interpretation than some kind of war machine.

Originally the word kentra, the Greek word translated "stings" in this verse, referred to goads or pricking irons used in torture. When the Lord appeared to Saul of Tarsus on the road to Damascus, He told Saul, "It is hard for you to kick against the goads" (Acts 26:14). Apparently, Saul—later called Paul—had been under sharp conviction for his persecution of believers. The conviction felt like pricking torture in his soul. The scorpions' stings will feel like sharp, pricking torture in those who do not have God's seal on their foreheads (Revelation 9:4). Scorpions' power to sting resides in their tails, and the demonic scorpions' stinging power resides in their tails.

Those who receive the locusts' stings suffer severely. Prior verses can be taken to mean that the demons are active for five months, or even that the effects of their stings last that long for anyone who is stung (Revelation 9:5)!