Joel: The Day of the LORD
|Disaster in the Land, 1:1-14||Day of the Lord, 1:15-2:11||Dependence on the Lord, 2:12-3:21|
|Destruction, 1:1-4||Imminent, 1:15-2:1||Turn to Me, 2:12-17|
|Awake 1:5-7||Illustrated, 2:2-11||I will answer, 2:18-3:21|
|Lament, 1:8-10||Restoration of the land, 2:18-27|
|Be ashamed, 1:11-12||Outpouring of the Spirit, 2:28-32|
|Lament, 1:13-14||Judgement of the Nations, 3:1-16a|
|Blessing for Israel, 3:16b-21|
The Day of the Lord is a phrase used repeatedly in the Old Testament as a reference to a time of judgement by God upon the nation of Israel and also upon the Gentile nations. (Note that it is not here a 24 hour day, but rather a reference to an undefined period of time.) Sometimes the reference is to a judgement that was to occur in the near future (Isa. 13:6, 9; Jer. 46:10) and has subsequently been fulfilled, although these are generally seen as but a foreshadowing of the final great Day of the Lord.
Joel, speaking of the day of the Lord, says “it shall come as destruction from the Almighty” (1:15). He goes on to say, “it is great and terrible; Who can endure it?” (2:11). He warns of cosmic disturbances that will precede this great day of God’s judgement (3:14-15). Then the Lord will roar from Zion, And utter His voice from Jerusalem; The heavens and earth will shake; But the Lord will be a shelter for His people, And the strength of the children of Israel” (3:16).
The Day of the Lord “will be a lengthy time period including both judgement and blessing. It will begin soon after the Rapture and will include the seven-year Tribulation, the return of the Messiah, the Millennium, and the making of the new heavens and new earth.” 
 Robert Chisholm, Bible Knowledge Commentary: Old Testament