Satan operates under a premise: you will be loyal to God only if He blesses you. Read it...
“Does Job fear God for nothing?” Satan replied. “Have you not put a hedge around him and his household and everything he has? You have blessed the work of his hands, so that his flocks and herds are spread throughout the land. But now stretch out your hand and strike everything he has, and he will surely curse you to your face” (Job 1:9-11).
You see what he’s saying? Satan thinks you praise God only when there are benefits attached to it. He thinks you live for God only when you’re going to get something out of it. So Satan views suffering as a way to strip away all those perks and expose you as a fraud.
Satan says, “The only reason you love God and live for him are for the blessings you get from him. Take those blessings away and I bet your praises will turn into curses.”
He sees suffering as a way to expose Christians as frauds... and you know as well as I, his tactic has been successful at times.
There's a sobering reality that surrounds Satan and his use of suffering: it's only in suffering what you really think and feel about God is revealed. Take away all the perks in life: a home to live in, a car to drive, fairly good health to sustain me, food, family, friends. Take it all away and all you have left is God. Is that enough? The only way to truly know what you think and feel about God is to strip away every possible ulterior motive you may have for loving him. That’s called suffering. That’s the only way to find out.