Revelation 11:5 in the King James Version
And if any man will hurt them, fire proceedeth out of their mouth, and devoureth their enemies: and if any man will hurt them, he must in this manner be killed.
Context
4 These are the two olive trees and the two lamp stands, standing before the Lord of the earth.
5 If anyone desires to harm them, fire proceeds out of their mouth and devours their enemies. If anyone desires to harm them, he must be killed in this way.
6 These have the power to shut up the sky, that it may not rain during the days of their prophecy. They have power over the waters, to turn them into blood, and to strike the earth with every plague, as often as they desire.