First Amendment Defense Act This bill prohibits the federal government from taking discriminatory action against a person on the basis that such person speaks or acts in accordance with a religious belief or moral conviction that: (1) marriage is or should be recognized as the union of one man and one woman or two individuals as recognized under federal law, or (2) sexual relations outside marriage are improper. The bill defines "person" as any person regardless of religious affiliation, except publicly traded for-profit entities; federal employees acting within the scope of their employment; federal for-profit contractors acting within the scope of their contract; or hospitals and other health care entities with respect to visitation, recognition of a designated representative for health care decisions, or refusal to provide medical treatment necessary to cure an illness or injury.