Joel 2

The prophet sounds a terrifying alarm on Mount Zion, warning of the approaching Day of the Lord. He describes a mighty, dark army (which symbolizes either a literal army or the locusts) as a fire that devours before them, moving with unstoppable military precision. God commands the people to return to Him with all their heart, with fasting, weeping, and mourning. God promises that if they genuinely repent, He will remove the enemy, restore the years the locusts have eaten, and pour out His Spirit on all flesh (a prophecy fulfilled at Pentecost).