Fan

Fan (or winnowing shovel) was the agricultural implement used to separate grain from chaff after threshing. The grain was threshed on an open floor — typically a flat rock on a hilltop — and then the threshed mass was tossed into the air with a wooden shovel or fork. The wind carried the lighter chaff away while the heavier grain fell back to the floor (Isaiah 30:24; Jeremiah 15:7).

The image of winnowing provided a powerful biblical metaphor for divine judgment. God as a divine winnower separates the righteous from the wicked just as grain is separated from chaff. Jeremiah 15:7 uses the image to describe God's judgment on Israel. John the Baptist employed it for Christ: "His winnowing fan is in his hand, and he will thoroughly purge his floor, and gather his wheat into the garner; but he will burn up the chaff with unquenchable fire" (Matthew 3:12). This eschatological use of the winnowing image became one of the most vivid pictures of final judgment in the Synoptic Gospels.