Your Mormon apparently doesn’t know very much about his own religion, but that is typical.
My argument is very simple. If the Catholic Church lost its valid priesthood and sacraments as early as 100 A.D. (which is what most Mormons seem to assert) then it couldn’t possibly have survived for another 1900 years. It would have disintegrated. But it didn’t. It survived and thrived. Therefore, the priesthood was not lost, the sacraments were and are valid, and the Great Apostasy is a lie.
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