Today’s sunday School lesson at my wife’s LDS (Mormon) church was on baptism for the dead - 1 Corinthians 15:29.
To cut a very long and boring story short, at the end of the meeting one of the LDS High Priests came up to me and started ranting against the Catholics. He has no idea that I want to be Catholic. Anyway, I was polite and listened to him. Then he said that Catholics believed in baptisms for the dead until about 340AD. I asked him to give me a reference as to where his information came from. The internet of course was his reply.
Anyway, I assured him that he was incorrect, that the orthodox Catholic church never did. Perhaps heretic groups did, but he assured me that it was the orthodox church did (i.e. mainstream, not the Eastern church).
So, my question is this: is anyone aware of evidence or writings that shows where he might be getting his erroneous belief from. Was there a heretic group that believe such ?