The prophet Joel ministered in Judah at a time when drought and a plague of locusts had devastated the economy. He used the phrase “the day of the Lord (1:15; 2:1, 11, 31; 3:14) to describe both their present calamity (1:1–2:27) and the future judgment that would come upon the whole world (2:28–3:21). God’s “army” of locusts (2:11, 20, 25) was but a picture of a future army that would invade the land in the last days. Joel called the nation to repent (2:12–17) and promised that the Lord would forgive and bless them (2:18–27). He also promised blessings in the last days when Israel’s tribulation would be ended (2:28–32; 3:18–21). God’s message of judgment is not left without a promise of hope.
Campbell Morgan wrote, “It is always the day of the Lord.” No matter what calamities may come to men and nations, He is always in control, and these calamities remind us of the greater judgment yet to come.