Obj. 3: Further, every sin committed against God is a mortal sin, because mortal sin alone turns man away from God. Now scandal is a sin against God, for the Apostle says (1 Cor.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic sin God
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

“18:6: "He that shall scandalize one of these little ones, that believe in Me, it were better for him that a mill-stone should be hanged about his neck, and that he should be drowned in the depth of the sea." For, as Jerome says on this passage, "it is much better to receive a brief punishment for a fault, than to await everlasting torments." Therefore scandal is a mortal sin.
Obj. 3: Further, every sin committed against God is a mortal sin, because mortal sin alone turns man away from God. Now scandal is a sin against God, for the Apostle says (1 Cor. 8:12) : "When you wound the weak conscience of the brethren [*Vulg.: 'When you sin thus against the brethren and wound their weak conscience'] , you sin against Christ." Therefore scandal is always a mortal sin.
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