Saint Augustine: The City of God (De Civitate Dei)

It pleased divine providence to prepare in the future good things for the just, which the unjust will not enjoy, and evils for the impious, by which the good will not be tormented. However, He willed that these temporal goods and evils be common to both, so that good things might not be sought too greedily,
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since the wicked are also seen to possess them; nor should evils be shamefully avoided, by which the good are also frequently affected.

It matters a great deal, however, what the use of those things is, whether they are called prosperous or adverse.
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For the good man is neither exalted by temporal goods nor broken by evils; the wicked man, however, is punished by this kind of misfortune because he is corrupted by prosperity. Yet God often shows His operation more evidently even in the distribution of these things.
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For if every sin were punished with manifest penalty now, it would be thought that nothing is reserved for the final judgment; on the other hand, if divinity did not openly punish any sin now, it would be believed that no divine providence exists. Similarly in prosperous things, if God did not grant them to certain ones who ask with most evident generosity, we would not say that these things pertain to Him; likewise, if He gave them to all who ask, we would think that one should serve Him only for the sake of such
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rewards, and such service would not make us pious, but rather covetous and greedy. Since these things are so, even if the good and the wicked are equally afflicted, they are not undistinguished because that which both have suffered is not distinguished. For the dissimilarity of those who suffer remains even in the similarity of the sufferings, and though under the same torment, virtue and vice are not the same. For just as under one fire gold glows while chaff smokes, and under the same threshing sled stalks are crushed while grain is purified, and dregs are not confused with oil because they are squeezed by the same press, so one and the same force striking the good tests, purifies, and refines, while it damns, wastes, and exterminates the wicked. Hence in the same affliction, the wicked detest and blaspheme God.