1:4 That which the palmerworm hath left hath the locust eaten; and that which the locust hath left hath the cankerworm eaten; and that which the cankerworm hath left hath the caterpiller eaten.
The palmerworm, locust, etc., are thought to be different forms, at different stages of development, of one insect. The essential fact is that, according to the usual method of the Spirit in prophecy, some local circumstance is shown to be of spiritual significance, and is made the occasion of a far-reaching prophecy (e.g.) Isaiah 7:1-14 where the Syrian invasion and the unbelief of Ahaz give occasion to the great prophecy of verse 14. Here in Joel a plague of devouring insects is shown to have spiritual significance Joel 1:13 Joel 1:14 and is made the occasion of the prophecy of the day of the Lord, not yet fulfilled. (See Scofield "Isaiah 2:12") . This is more developed in Joel 2., where the literal locusts are left behind, and the future day of Jehovah fills the scene.
The whole picture is of the end-time of this present age, of the "times of the Gentiles" Luke 21:24 ; Revelation 16:14 of the battle of Armageddon ; Revelation 16:14 ; 19:11-21 of the regathering of Israel. (See Scofield "Romans 11:26") and of kingdom blessing. It is remarkable that Joel, coming at the very beginning of written prophecy (B.C. 836), gives the fullest view of the consummation of all written prophecy.
The order of events is:
(4) the answer of Jehovah Joel 2:18-27