1. Revelation 9:10 (ESV)
  2. Exposition

Why does the Holy Spirit have John repeat that these locusts have power to hurt people for five months with their tails?

Revelation 9:10 (ESV)

10 They have tails and stings like scorpions, and their power to hurt people for five months is in their tails.

We already know this information from Revelation 9:3–5. But this is the point of the fifth trumpet, namely, that demons would hurt and torment people in agonizing fashion, with no escape. By piling up these images from Revelation 9:7–10 John draws a terrifying picture of the Lord’s judgment on those who have rejected the gospel (namely, those not sealed, Revelation 9:4).