His reasons for staying Catholic seem to be the same reasons many people remain in various other Christian denominations–and also, the reason many stay in non-Christian faiths, as well:
They believe their faith has the “remedy” to heal and restore. They believe love became “incarnate” by a human/divine person. They feel a longing and “ache” for something eternal and a passionate union with God, and they believe their faith is the “answer” to that longing.
These seem to be similar longings many people of religion want to fill…and each feels their own faith fills it. And so they remain.
I don’t know how well-known this writer is. Perhaps, in Catholic circles?
My writer and publisher and editor friends haven’t heard of him by name.
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