Now the good of grace is better than the good of nature. Hence, since natural forms necessarily come to disposed matter, much more does it seem that grace is necessarily bestowed on whoever prepares himself for grace.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic grace good
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

“But if the cause be removed, the effect must needs be removed also. Therefore, if anyone is willing to receive grace it is bestowed on them of necessity.
Obj. 3: Further, good is diffusive of itself, as appears from Dionysius (Div. Nom. iv) . Now the good of grace is better than the good of nature. Hence, since natural forms necessarily come to disposed matter, much more does it seem that grace is necessarily bestowed on whoever prepares himself for grace. On the contrary, Man is compared to God as clay to the potter, according to Jer. 18:6: "As clay is in the hand of the potter, so are you in My hand." But however much the clay is prepared, it does not necessarily receive its shape from the potter.” source