A perverse intention perverts the action of the one who has such an intention, not the action of another.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic action intention
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“Consequently, the minister who conforms his intention to the Church as to the former rectitude, but not as to the latter, perfects the sacrament indeed, but gains no merit for himself. Reply Obj. 2: The intention of mimicry or fun excludes the first kind of right intention, necessary for the validity of a sacrament. Consequently, there is no comparison. Reply Obj. 3: A perverse intention perverts the action of the one who has such an intention, not the action of another. Consequently, the perverse intention of the minister perverts the sacrament in so far as it is his action: not in so far as it is the action of Christ, Whose minister he is. It is just as if the servant” source