Objection 1: It would seem that self-love is not the source of every sin. For that which is good and right in itself is not the proper cause of sin.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic sin love
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

“3: It is in the will's power to give or refuse its consent to what passion inclines us to do, and it is in this sense that our appetite is said to be under us; and yet this consent or dissent of the will is hindered in the way already explained (A. 1). ________________________
FOURTH ARTICLE [I-II, Q. 77, Art. 4]
Whether Self-love Is the Source of Every Sin?
Objection 1: It would seem that self-love is not the source of every sin. For that which is good and right in itself is not the proper cause of sin. Now love of self is a good and right thing in itself: wherefore man is commanded to love his neighbor as himself (Lev. 19:18). Therefore self-love cannot be the proper cause of sin.
Obj. 2: Further, the Apostle says (Rom.” source