Charles Ellicott Commentary Revelation 9:4

"And it was said unto them that they should not hurt the grass of the earth, neither any green thing, neither any tree, but only such men as have not the seal of God on their foreheads." — Revelation 9:4 (ASV)

And it was commanded . . . — This should be translated: It was commanded them that they should not injure the grass of the earth, nor any green thing, nor any tree; but only (or, except) the men who do not have the seal of God on their foreheads.

The locusts that are sent not to injure the vegetation are clearly not literal locusts. The security of those who have the seal of God on their foreheads (those who were described as sealed, and so assured of safety against the tempest blast—see Revelation 7:1-3 and following) may confirm us in this view. Whatever the plague may be, it is one that cannot injure God’s children. “Nothing,” Christ has said, “shall by any means hurt you. I give you power to tread on serpents and scorpions, and over all the power of the enemy” (Luke 10:19).

It is interesting and suggestive to notice that this promise of our Lord was given immediately after the saying, “I beheld Satan as lightning fall from heaven,” as the safety of the sealed ones is mentioned here after the vision of the star fallen from heaven. The coincidence is hardly undesigned; at least, the sense in which we understand the danger from which Christ promised His disciples protection may afford us a guiding meaning here.

Now, no one has maintained that Christ promised His disciples entire freedom from danger, pain, and death. He said, “They shall persecute you and kill you; ye shall be hated of all men for My name’s sake, but he that endureth to the end shall be saved.” No real injury can happen to them; pain and death might be encountered, but all things work together for their higher good. They have a joy that no pain or peril can take away; they have a joy in this (it is from the same chapter as above—Luke 10:20), that their “names are written in heaven.”

For such, death has no sting, the grave no victory. They meet famine and nakedness, and peril and sword; but in these they are more than conquerors. No plague can hurt those who have the seal of God on their foreheads. A plague from which those whose way is through tribulation are exempt can hardly be a physical one.