Ah, thank you. Now that you mention it, I had heard that before, and must have forgotten. Thanks!
Theology of the Body is the name given to the late Pope John Paull II's teachings on...well, life, but basically what it means to be human, to have a body and a soul, and how that ties in to the story of Creation, and Jesus' life, and redemption and marriage, and celibacy, and of course sex.
Very difficult to summarize it, since it is practically a whole system of philosophy/theology. Christopher West is the main person who speaks and writes about it in terms understandable to the layman

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