The threshing floors will be full of wheat, and the vats will overflow with new wine and oil.
He goes on with the same subject in this verse, and shows the effects of rain; for when the earth is irrigated and satiated with sufficient moisture, it brings forth fruit, rich and plentiful. God then will cause that the rains shall not be useless, for the floors shall be full of wheat, and the fats shall overflow with wine as well as oil.
The barns overflow with grain, the vats run over with wine and oil, this is God repaying the years the locusts consumed. He uses 'years' with poetical force to express the violence and scale of devastation, and now He reverses it entirely. The same God who commanded that plague as His army now commands abundance, and His people will know Him as their God alone.
AI summary
Commenting on Joel 2:24-25
And the floors shall be full of wheat,.... The churches of Christ, which will now be in Judea, and in the Gentile world, which are his "floors", Mat 3:12; and which will be set up everywhere through the preaching of the Gospel, the descent of the former and latter rain; these will be full of precious souls gathered in, compared to wheat, and of the...