Nothing is more hateful than despair, for the man that has it loses his constancy both in the every day toils of this life, and, what is worse, in the battle of faith.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic despair constancy
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

“If, however, despair be compared to the other two sins from our point of view, then despair is more dangerous, since hope withdraws us from evils and induces us to seek for good things, so that when hope is given up, men rush headlong into sin, and are drawn away from good works. Wherefore a gloss on Prov. 24:10, "If thou lose hope being weary in the day of distress, thy strength shall be diminished," says: "Nothing is more hateful than despair, for the man that has it loses his constancy both in the every day toils of this life, and, what is worse, in the battle of faith." And Isidore says (De Sum. Bono ii, 14) : "To commit a crime is to kill the soul, but to despair is to fall into hell." [And from this the response to the objections is evident.] _______________________” source