In the 6th, 7th, 8th, 9th centuries, Augustinian theologians in the Western Catholic world

debated about and thought about in depth the question of the relationship between the three

bodies, the body of Christ in his glory, the body of Christ truly present on the altar in the mass, and the body of Christ

that is the church, according to St. Paul. St. Paul does not call the church the mystical body.

He calls the church the body of Christ. Now, there was a great deal of debate on this subject.

There were important books written on this in the 20th century

that one can consult, that have a lot of historical reflections. And what I just want to note here

for the purposes of getting started is that in the 13th century, really probably already in the 12th

century, a threefold schema emerged in the language of

the church in the mainstream language of Scholastic Theologians that Aquinas presupposes, he doesn't

come up with this, and he makes use of it. It's to talk about the Eucharistic body of the

Lord on the altar as the true body of Christ, Verim Chloropus, the famous hymn of Aquinas that we sing, and the body

of the church as the mystical body.

And in Aquinas' theology, he wants to think about how the Eugris effectuates or creates the

grace of the church.

Well, you might say gives, not creates, it's not right, the right word, but is the instrumental

source, the Eucharist is the instrumental source of the grace of charity that binds the church

together.

So how does communion in the true body and blood of Christ on the altar create or beget the church, you might say,

as the mystical body of Christ in charity?

How is the true body of Christ on the altar the instrument through which the mystical body of the church is knit together in charity?

So that's just the first overall concept.

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