We are nourished from the same things of which we are made, but they do not come to us in the same way; for those out of which we are made come to us through generation, while the same, as nourishing us, come to us through being eaten.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic eating generation
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

“"In order to commend more earnestly the death of this mystery, our Saviour willed this last act to be fixed in the hearts and memories of the disciples whom He was about to quit for the Passion." Reply Obj. 1: We are nourished from the same things of which we are made, but they do not come to us in the same way; for those out of which we are made come to us through generation, while the same, as nourishing us, come to us through being eaten. Hence, as we are new-born in Christ through Baptism, so through the Eucharist we eat Christ. Reply Obj. 2: The Eucharist is the perfect sacrament of our Lord's Passion, as containing Christ crucified;” source