He who does an injustice in small matters falls short of the perfection of an unjust deed, in so far as what he does may be deemed not altogether contrary to the will of the person who suffers therefrom: for instance, if a man take an apple or some such thing from another man, in which case it is probable that the latter is not hurt or displeased.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic perfection suffering
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“, and which deserves pardon, and not to ignorance of the law which does not excuse: and he who does an injustice through ignorance, does no injustice except accidentally, as stated above (A. 2) Reply Obj. 2: He who does an injustice in small matters falls short of the perfection of an unjust deed, in so far as what he does may be deemed not altogether contrary to the will of the person who suffers therefrom: for instance, if a man take an apple or some such thing from another man, in which case it is probable that the latter is not hurt or displeased. Reply Obj. 3: The sins which are contrary to the other virtues are not always hurtful to another person, but imply a disorder affecting human passions; hence there is no comparison. _______________________” source