Now this, also, ought to be added, that although either fatherly favor and beneficence or severity of judgment often shine forth in the whole course of providence, nevertheless sometimes the causes of the events are hidden.
So the thought creeps in that human affairs turn and whirl at the blind urge of fortune; or the flesh incites us to contradiction, as if God were making sport of men by throwing them like balls. It is, indeed, true that if we had quiet and composed minds ready to learn, the final outcome would show that God always has the best reason for his plan:
either to instruct his own people in patience,
or to correct their wicked affections and tame their lust,
or to subjugate them to self-denial,
or to rouse them from sluggishness;
again, to bring low the proud, to shatter the cunning of the impious and to overthrow their devices.
Yet however hidden and fugitive from our point of view the causes may be, we must hold that they are surely laid up with him, and hence we must exclaim with David: “Great, O God, are the wondrous deeds that thou hast done, and thy thoughts toward us cannot be reckoned; if I try to speak, they would be more than can be told” [Ps. 40:5]. (Institutes of the Christian Religion, 1.17.1)