We shall find five times the expression “the day of the Lord” in this book. As you know, this refers to a day after the believers are caught up to be with the Lord. Then the punishments from God shall fall on this earth, particularly on Israel.
A terrible pestilence of flies, locusts and caterpillars, which seem to have eaten everything in sight. The land of Israel is left empty. This has two purposes: (1) To awaken the people to realize they had turned away from the Lord Who loved them, and (2) to remind them that a much more awful day of punishment would come on their land. Though almost 2,800 years have gone by since Joel wrote this book, “the day of the Lord” — “D” on your chart — hasn’t come yet. But let’s not think that it’s not close. The pestilence wasn’t just a piece of bad luck, as people say. God had a message for those people — and He has a message for us, when He allows a great sorrow to come to us.
V.15 This is the first reference to that awful “day.” Judah had been living carelessly, paying little or no attention to God’s pleadings with them. Now God reminds them of the coming of “the day of the Lord.”