Albert Barnes Commentary Revelation 7:3

"saying, Hurt not the earth, neither the sea, nor the trees, till we shall have sealed the servants of our God on their foreheads." — Revelation 7:3 (ASV)

Saying, Hurt not the earth, neither the sea, etc. Let the winds be restrained until what is here designated is done. These destroying angels were commanded to suspend the work of destruction until the servants of God could be made secure. The division here, as in Revelation 7:1, of the "earth, the sea, and the trees," seems to include everything—water, land, and the produce of the earth. Nothing was to be injured until the angel should designate the true servants of God.

Till we have sealed the servants of our God. The use of the plural "we" seems to denote that he did not expect to do it alone. Who were to be associated with him, whether angels or men, he does not intimate; but the work was evidently such that it demanded the agency of more than one.

In their foreheads. See the notes on Revelation 7:2; compare with Ezekiel 9:4-5. A mark so placed on the forehead would be conspicuous, and would be something that could be immediately recognized if destruction should spread over the world. The fulfillment of this is to be found in two things:

1. in something that would be conspicuous or prominent—so that it could be seen; and
2. in the mark being of such a nature or character that it would be a proper designation of the fact that they were the true servants of God.