just as the imperfect, which does not attain the perfection of its species, is divided in contrast with the perfect.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic perfection contrast
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“That sacramental eating which is also a spiritual eating is not divided in contrast with spiritual eating, but is included under it; but that sacramental eating which does not secure the effect, is divided in contrast with spiritual eating; just as the imperfect, which does not attain the perfection of its species, is divided in contrast with the perfect. Reply Obj. 3: As stated above (Q. 73, A. 3) , the effect of the sacrament can be secured by every man if he receive it in desire, though not in reality. Consequently, just as some are baptized with the Baptism of desire, through their desire of baptism, before being baptized in the Baptism of water;” source