What do you call people who convert from one religion to another?

An Anthropologist is one good answer, they study all religions as a consistently arrising social phenomenon. It is a social institution on all levels of social order, hard to detect in lower primates but i suspect it is there in a nacent form. So what is going on? Humanity is working to assure the growth of consciousness will have a path forward anon, and that the kids do not have to make the same foolish mistakes the ancestors made; we have taboo, precept, and commandment-Word!

To honour the efforts of all religions and to thereby transcend the divisive is to aproach religion from the state of intellectual freedom. This being the case, lets call this intrepid soul, free. So, a person who believes in all religions is free; that is my answer.

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Another answer is - one who follows the Baha'i faith. (http://www.bahai.org/)