Revelation 9:19

19 For the power of the horses is in their mouths, and in their tails. For their tails are like serpents, and have heads, and with them they harm.

Revelation 9:19 In-Context

17 Thus I saw the horses in the vision, and those who sat on them, having breastplates of fiery red, hyacinth blue, and sulfur yellow; and the heads of lions. Out of their mouths proceed fire, smoke, and sulfur.
18 By these three plagues were one third of mankind killed: by the fire, the smoke, and the sulfur, which proceeded out of their mouths.
19 For the power of the horses is in their mouths, and in their tails. For their tails are like serpents, and have heads, and with them they harm.
20 The rest of mankind, who were not killed with these plagues, didn't repent of the works of their hands, that they wouldn't worship demons, and the idols of gold, and of silver, and of brass, and of stone, and of wood; which can neither see, nor hear, nor walk.
21 They didn't repent of their murders, nor of their sorceries, nor of their sexual immorality, nor of their thefts.
The Hebrew Names Version is in the public domain.