They were told not to harm the grass of the earth or any plant or tree, but only those who did not have the seal of God on their foreheads.

Exodus 12:23
When the LORD passes through to strike down the Egyptians, He will see the blood on the top and sides of the doorframe and will pass over that doorway; so He will not allow the destroyer to enter your houses and strike you down.

Ezekiel 9:4
"Go throughout the city of Jerusalem," said the LORD, "and put a mark on the foreheads of the men sighing and groaning over all the abominations committed there."

Ezekiel 9:6
Slaughter the old men, the young men and maidens, the women and children; but do not go near anyone who has the mark. Now begin at My sanctuary." So they began with the elders who were before the temple.

Revelation 6:6
And I heard what sounded like a voice from among the four living creatures, saying, "A quart of wheat for a denarius, and three quarts of barley for a denarius, and do not harm the oil and wine."

Revelation 7:1
After this I saw four angels standing at the four corners of the earth, holding back its four winds so that no wind would blow on land or sea or on any tree.

Revelation 7:2
And I saw another angel ascending from the east, with the seal of the living God. And he called out in a loud voice to the four angels who had been given power to harm the land and the sea:

Revelation 7:3
"Do not harm the land or sea or trees until we have sealed the foreheads of the servants of our God."

Revelation 8:7
Then the first angel sounded his trumpet, and hail and fire mixed with blood were hurled down upon the earth. A third of the earth was burned up, along with a third of the trees and all the green grass.

And it was commanded them that they should not hurt the grass of the earth, neither any green thing, neither any tree; but only those men which have not the seal of God in their foreheads.