And it was commanded them that they should not hurt the grass of the earth, neither any green thing, neither any tree. The force of this plague is to fall directly upon mankind, not, as in the former judgments, upon the earth, and then indirectly upon men.
This appears to be stated with the greater plainness, because it might readily be inferred, from the nature of locusts, that the immediate object of their destructiveness would be the vegetation of the world.
But only those men which have not the seal of God in their foreheads; but only such men as have not, etc. (Revised Version; cf. Revelation 7:3, to which this is an allusion). Here, by proleipsis, the servants of God are described as "those that have the seal of God in their foreheads."
It is not stated, nor is it necessarily implied, that the seal is visible to man at the time of the infliction of this judgment upon the ungodly. In a similar way our Lord speaks of the elect (Matthew 24:22), not thereby implying that there is any visible manifestation by which the elect may be known to men, though known to God.
Thus also it is said in 2 Timothy 2:19, "The foundation of God standeth sure, having this seal, The Lord knoweth them that are his." The frequent use of the term to denote those who were sealed by baptism may have led to the employment of the expression in this place, as being equivalent to "the servants of God" (cf.
Ephesians 1:13; Ephesians 4:30; 2 Corinthians 1:22). The locusts may not hurt God's servants (see on 2 Timothy 2:3). Thus we are taught that God in reality preserves his own, though it may sometimes appear to man as though the innocent suffer with the guilty.