After these things, I saw four angels standing on the four corners of the earth, holding the four winds of the earth, that they should not blow upon the earth, nor upon the sea, nor on any tree. And I saw another angel ascending from the rising of the sun, having the sign of the living God; and he cried with a loud voice to the four angels, to whom it was given to hurt the earth and the sea, Saying: Hurt not the earth, nor the sea, nor the trees, till we sign the servants of our God in their foreheads.
Revelation 7:1-3