Matthew 3:12
His winnowing fork is in his hand, and he will clear his threshing floor and gather his wheat into the barn, but the chaff he will burn with unquenchable fire. The agricultural image of winnowing — throwing grain and chaff into the air so the wind separates them — is the image of judgment that separates what is valuable from what is not. The threshing floor is the whole human community; the wheat is those who bear genuine fruit; the chaff is the fruitless religious performance. The unquenchable fire is not threatened but announced as certain: the coming one carries the winnowing fork, and the floor will be cleared. Isaiah 66:24 speaks of the fire that will not be quenched; John appropriates the language of final judgment to describe what the arrival of the Messiah will bring.