I am a freemason.
Freemasonry is a social fraternity that studies morality through ritual, symbol and allegory, it makes good men better and provides more charity than any other group on the planet. But its not for everyone... It is a good organization to join though.
No churches ban membership in freemasonry, there are freemasons of every major religious tradition, protestant, catholic, luthern, presbyterian, judaism, islam, hinduism, buddhism, etc...
Damocles' explanation of freemasonry is no accurate in any way... there are very few books written by anti-masons that speak against freemasonry and those that do are writing fiction so they can cash in, literally, on the anti-mason conspiracy movement. no freemason would be involved in child pornography - this is offensive and a flat out lie.
freemasons have no position on a person's sexual preference...
the catholic church does not forbid its members to join, there are many, many catholic freemasons, including priests, bishops and cardinals.