The sun and the moon shall be darkened, and the stars shall withdraw their shining.
I have already explained this verse in chapter 2: the Prophet, as we then stated, describes in these words the terrible judgment of God, in order to shake off the indifference of men, who carelessly hear and despise all threatening, except the Lord storms their hearts.
This call to the nations to prepare war is spoken ironically: let all forces confederate against God if they dare. They are summoned to the battle of that great day when God shall judge the earth, gathering all nations to their ruin.
AI summary
Commenting on Joel 3:9-17
The sun and moon shall be darkened,.... Both the politic and ecclesiastic state of antichrist shall be ruined and destroyed; it shall "fare" with Rome Papal as it did with Rome Pagan, at the time of its dissolution; see Rev 6:12; and the stars shall withdraw their shining: antichristian princes and nobles in the civil state, and the clergy of all ranks in the church state, shall lose their glory.