If a Christian run business can refuse to hire a lesbian or gay man for religious reasons, can they refuse to hire somebody they consider a heretic for religious reasons?  perhaps an atheist, or agnostic?  Catholic or a Jew who does not believe Jesus is Lord? 
Emo Phillips
Once I saw this guy on a bridge about to  jump. I said, "Don't do it!" He said, "Nobody loves me." I said, "God  loves you. Do you believe in God?"
He  said, "Yes." I said, "Are you a Christian or a Jew?" He said, "A  Christian." I said, "Me, too! Protestant or Catholic?" He said,  "Protestant." I said, "Me, too! What franchise?" He said, "Baptist." I  said, "Me, too! Northern Baptist or Southern Baptist?" He said,  "Northern Baptist." I said, "Me, too! Northern Conservative Baptist or  Northern Liberal Baptist?"
He said,  "Northern Conservative Baptist." I said, "Me, too! Northern Conservative  Baptist Great Lakes Region, or Northern Conservative Baptist Eastern  Region?" He said, "Northern Conservative Baptist Great Lakes Region." I  said, "Me, too!"
Northern  Conservative†Baptist Great Lakes Region Council of 1879, or Northern  Conservative Baptist Great Lakes Region Council of 1912?" He said,  "Northern Conservative Baptist Great Lakes Region Council of 1912." I  said, "Die, heretic!" And I pushed him over.