What does the threshing floor symbolize in Second Samuel? How does it apply to us today?
I find two references to threshing floors in Second Samuel. One is at 2 Samuel 6:6, which says they were by Nachonís threshing floor when Uzzah touched the Ark of the Covenant and died. The other is in 2 Samuel 24:16-24. In that passage, an angel who is bringing a plague on Israel ends the plague at the threshing floor of Araunah the Jebusite. King David buys the site and sets up an altar to God to commemorate the end of the plague.
In both cases, the threshing floor does not symbolize anything except a place for processing grain. They are merely locations, and have no special spiritual symbolism.