Luke 22:31, “And the Lord said, Simon, Simon, behold, Satan hath desired to have you, that he may sift you as wheat.”
Sifting wheat is a harvesting term. The farmers would take the stalks of wheat. They would begin to shake and beat the stalks to disconnect the wheat from the chaff. Once disconnected, the farmer would take the pile in front of them and toss it in the air. The grains of wheat are heavy enough, so it would fall right back to the ground, but the chaff would get caught in the wind and blow away. Nowadays, they have it in a bucket. They slowly pour one bucket into another bucket with a fan blowing. As the wheat/chaff mixture comes out, the wind blows away the chaff, and the wheat falls into the other bucket.
Satan desires to sift Christians as wheat. Satan wants to shake and beat Christians enough that they will just blow away when opposition comes. We must be grounded in righteousness, so we cannot be shaken by the devil’s temptations. Colossians 2:7, “Rooted and built up in him, and stablished in the faith, as ye have been taught, abounding therein with thanksgiving.”