For a just punishment is equal to the fault, since justice is equality
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic equality punishment
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17897/pg17897-images.html

Context

“and the same answer applies to the Third Objection. ________________________ THIRD ARTICLE [I-II, Q. 87, Art. 3] Whether Any Sin Incurs a Debt of Eternal Punishment? Objection 1: It would seem that no sin incurs a debt of eternal punishment. For a just punishment is equal to the fault, since justice is equality: wherefore it is written (Isa. 27:8) : "In measure against measure, when it shall be cast off, thou shalt judge it." Now sin is temporal. Therefore it does not incur a debt of eternal punishment. Obj.” source