From Institutes:

1. No mere “permission”!
From other passages, in which God is said to draw or bend Satan himself, and all the reprobate, to his will, a more difficult question arises. For the carnal mind can scarcely comprehend how, when acting by their means, he contracts no taint from their impurity, nay, how, in a common operation, he is exempt from all guilt, and can justly condemn his own ministers. Hence a distinction has been invented between doing and permitting because to many it seemed altogether inexplicable how Satan and all the wicked are so under the hand and authority of God, that he directs their malice to whatever end he pleases, and employs their iniquities to execute his judgements. The modesty of those who are thus alarmed at the appearance of absurdity might perhaps be excused, did they not endeavour to vindicate the justice of God from every semblance of stigma by defending an untruth. It seems absurd that man should be blinded by the will and command of God, and yet be forthwith punished for his blindness. Hence, recourse is had to the evasion that this is done only by the permission, and not also by the will of God. He himself, however, openly declaring that he does this, repudiates the evasion. That men do nothing save at the secret instigation of God, and do not discuss and deliberate on any thing but what he has previously decreed with himself and brings to pass by his secret direction, is proved by numberless clear passages of Scripture.

Calvin, John. The John Calvin Collection: 12 Classic Works (Kindle Locations 3529-3539). . Kindle Edition.