

Honestly, I don't know much about threshing. I learned a bit by searching the Scriptures this morning:
There are two Hebrew words for 'thresh.' Both mean to trample, or tread down. Before the invention of modern farm equipment, sheaves of harvested grain were brought to the threshing floor, where they were either trampled by animals (oxen, donkeys, etc.) or beaten by hand with 'flails', as pictured above. This process separated the grain from the straw. The grain would then be kept for seed, or used to make bread. The straw was used as bedding for animals, or simply burned.
God speaks of 'threshing' in three contexts:
1) He warns the nations that they will be 'threshed' in judgment:
"You threshed the nations in anger..." Habakkuk 3:12
"His breath is like an overflowing stream that reaches up to the neck
to sift the nations with the sieve of destruction." Isaiah 30:28
2) John the Baptist describes the threshing and winnowing of God's people:
whose sandals I am not worthy to carry,
He will baptize you with the Holy Spirit and fire.
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."
Matthew 3:11-12
that he might sift you like wheat.
But I have prayed for you that your faith may not fail."
Luke 22:31
Jesus doesn't leave it there, however! He continues:
"AND WHEN YOU HAVE TURNED AGAIN,
STRENGTHEN YOUR BROTHERS."

James, the brother of Jesus and author of the letter which bears his name, writes:
"Count it all joy, my brothers, when you meet trials of various kinds, for you know that the testing of your faith produces steadfastness. And let steadfastness have its full effect, that you may be perfect and complete, lacking in nothing." (James 1:2-4)
The threshing floor is a place of redemption
Naomi told Ruth in Ruth 3:2
We seasoned Christians are adept at justifying our sins...impurity, deceit, enmity, strife, anger, jealousy, rivalries, dissension, division, unlimited forms of idolatry... The last thing we want to do is confess and be cleansed. We have a Kinsman Redeemer who invites us to be washed and lie down at His feet...
Lord, strip me of this chaff and fill me with the fruit of Your Spirit...
or I can allow the Lord to remove my 'chaff' in the shaking!
"For the one who sows to the flesh will from the flesh reap corruption,
but the one who sows to the Spirit will from the Spirit reap eternal life."
Galatians 6:8