For generation is change from non-existence to existence, and is opposed to corruption
 Thomas Aquinas, Summa Theologica (1274). copy citation

add
Author Thomas Aquinas
Source Summa Theologica
Topic corruption change
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17611/pg17611-images.html

Context

“God, Who is the first principle of all things, may be compared to things created as the architect is to things designed. _______________________ SECOND ARTICLE [I, Q. 27, Art. 2] Whether Any Procession in God Can Be Called Generation? Objection 1: It would seem that no procession in God can be called generation. For generation is change from non-existence to existence, and is opposed to corruption; while matter is the subject of both. Nothing of all this belongs to God. Therefore generation cannot exist in God. Obj. 2: Further, procession exists in God, according to an intelligible mode, as above explained” source