"And when he turns away," meaning: when he leaves you, "he strives throughout the land to cause corruption therein," up to the end of the verse.

Al-Kalbi said: It was revealed regarding al-Akhnas ibn Shariq al-Thaqafi, who was a fierce opponent. As for his destruction of crops and livestock, it means: he severed the ties of kinship that [existed] between him and the tribe of Thaqif; he attacked them at night, destroyed their livestock, and burned their crops. He was pleasant in appearance but corrupt in character.