I think this may be a good quote to help us understand how God can use evil and/or sin. Just because God uses sin and evil, He is not guilty of wrongdoing. And He can still be good even if He uses sin, evil, and evil people. All things, not some or most, but…
All things work together for good.
This expression “work together” refers to medicine. Several poisonous ingredients put together, being tempered by the skill of the apothecary, make a sovereign medicine, and work together for the good of the patient. So all God’s providences being divinely tempered and sanctified, do work together for the best to the saints. He who loves God and is called according to His purpose, may rest assured that every thing in the world shall be for his good. This is a Christian’s cordial, which may warm him — make him like Jonathan who, when he had tasted the honey at the end of the rod, “his eyes were enlightened” (I Sam. xiv. 27). Why should a Christian destroy himself? Why should he kill himself with care, when all things shall sweetly concur, yea, conspire for his good?
~Thomas Watson, from All Things For Good, page 11; Banner of Truth Trust
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