this clip from EWTN's "Tolkien's 'The Lord of the Rings:' A Catholic Worldview" portraying a debate between C.S. Lewis and J.R.R. Tolkien on whether or not myths are lies. This debate was ultimately instrumental in C.S. Lewis's conversion to Christianity.
Tolkien, a devout Roman Catholic, filtered a Catholic worldview into LotR, mostly during the writing of his second draft. This is not always obvious on a literal level (e.g., there is no mention of any sort of "god," much less a one true God in LotR). But, then again, sometimes it is (e.g., the Elvin Lembas bread that keeps its eater full for days). Moreso, the significance and symbolism of Catholic beliefs are woven throughout the characters and storylines, and are quite obvious from a meta view.
For deeper list of relevant resources, please visit The Catholic Imagination of JRR Tolkien page.