In his time (in the book of Joel this is immediately after repentance), God comes into action with his salvation! This is the great turning point in the book. God does this more often (see e.g., Psalm 32:1–11) and how! His heart speaks. His love for his people is anchored deep inside and it breaks forth in words and deeds, bursting with grace and mercy. Everything shows how much God saves and desires to live in harmony and love with his people. In a concrete way, all that is needed for nourishment, sustenance, and joy in life flows forth to his people. The nations surrounding God’s people see it and gain admiration for them. The enemies are radically destroyed (the northerner is probably the enemy, Assyria, who carried off the Ten Tribe Kingdom). It does not even say in these verses that Israel is going to concretely confess its guilt. We do assume it because God is now going to stand up for his people (the reversal), but it is not stated here in as many words. The emphasis in these verses is on God who saves. Your repentance and conversion are not the basis of salvation. Instead, it is God’s love, which proceeds from himself. Therefore, all the emphasis falls on that action.