Lots of Catholics have incredible credentials and spout heresy. Credentials are not the issue. Constant teaching and non-contradicting development os same are issue.
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Then WHY did you start this whole conversation by attacking Dr. Luther’s credentials?
Wait, don’t answer that; I’m pretty sure I know.
I've concluded that it's due to moon phases. "Luther BAD" now, but wait a week or two and he'll be good again, I promise, having watched it on here for over a decade. Round and round it goes with poor ol' Martin Luther. Makes your head spin.
As I remember, I questioned his hubris, not his credentials