Actually, when someone is initiated the very first thing they are told is that the FM oath in no way encroaches upon their duty to God.

Therefore, if there is anything in that oath that you consider to be against God it is automatically null and void.

Technically this is in violation of that oath, but here it is:

vows of fidelity are required; but let me assure you that in those vows there is nothing incompatible with your civil, moral, or religious duties,