The name Joel means “Yahweh is God.” Little is known about the prophet, who was probably from Judah. It is likely that he ministered during a national calamity sometime after Judah returned from exile in Babylon. The primary theme in the book of Joel is the “day of the Lord”—a time when the presence of the Lord will bring both judgment and deliverance. Joel teaches that, while the day of the Lord will bring destruction on the nations, it will also be a time of salvation for God’s people. Judah will be the means through which God pours out his Spirit on all people (2:28–32), and he will preserve them against all who seek to destroy them. (Joel 2:11–14)