“ Now just as the involuntary deserves neither punishment nor reward in the accomplishment of good or evil deeds, so neither does it lessen reward or punishment, if a man through simple involuntariness fail to do good or evil. ”
 Thomas Aquinas, Summa Theologica (1274). copy citation

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“Wherefore the will is not perfect, unless it be such that, given the opportunity, it realizes the operation. But if this prove impossible, as long as the will is perfect, so as to realize the operation if it could; the lack of perfection derived from the external action, is simply involuntary. Now just as the involuntary deserves neither punishment nor reward in the accomplishment of good or evil deeds, so neither does it lessen reward or punishment, if a man through simple involuntariness fail to do good or evil. Reply Obj. 1: Chrysostom is speaking of the case where a man's will is complete, and does not refrain from the deed save through the impossibility of achievement.
Reply Obj. 2: This argument applies to that goodness which the external action derives from the will as tending to the end.” source