In my opinion as a believing and practicing Roman Catholic:
1. Christian businesses should not refuse to provide their products and services to gay persons.
If you provide a moral product or service, how is it immoral to provide it to a person who is gay? All of your customers are sinners, and so are you, so you cannot claim that the sins of one group of customers somehow justifies refusing them service. It is not moral to refuse to provide food, clothing, shelter, medical care, or other necessities to someone based on their sexual orientation or marital status (e.g. same-sex couples). I would also say that it is not moral to refuse non-essential products or services. Each person has responsibility for his or her own choices in life. You are not the judge over the lives of others, so that you would decide that they don’t deserve to be able to use your product or service.
If a fellow Catholic commits a grave sin against religion, such as apostasy, heresy, or schism, would you deny him the products or services of your company? No Catholic behaves in such a manner. And sins against religion are worse than sexual sins. Moreover, a large percentage of Catholics are guilty and unrepentant from objective mortal sin, including sexual sins, contraception, abortifacient contraception, and heresy. Peter, wash your nets.
2. I support laws, well-written and with a reasonable scope, to prohibit discrimination based on religion, race or ethnicity, sexual orientation, marital status, and other factors.
There is no sin for a Catholic Christian in providing a moral product or service to any law-abiding person. And the government has a legitimate interest and authority to ensure fair treatment for all persons, so that everyone can enjoy the benefits of the society in which they live. God gave each of us the gifts of reason and free will, so that we could make our own decisions based on our own understanding. So we faithful Catholic Christians have no right to impose our understanding on others.
Furthermore, I notice that, among my fellow Catholics, there is much disagreement about what is and is not moral. Even when the Church has a definitive teaching, many Catholics claim that the teaching is to be interpreted or applied in some manner that permits them to do things that other Catholics consider gravely immoral. So if we cannot agree among ourselves on grave matters of morality, how can we say to non-Catholics that they must abide by our understanding? Peter, mend your nets.
3. On the specific narrow topic of same-sex weddings, I do not believe it is immoral for a Catholic Christian business owner or employee to provide services such as: a wedding cake, flowers, music, food, photography, garments, or other things to a gay wedding. Under Catholic moral teaching, this type of participation is remote material cooperation. It is moral because you are not doing anything immoral yourself. You do not approve of same-sex weddings, so your cooperation is not explicit. You are not directly assisting anyone in an intrinsically evil act, so your act is not formal cooperation (which is always immoral). And as long as the reasonably anticipated good consequences of your act morally outweigh any reasonably anticipated bad consequences, you have three good fonts of morality and therefore a moral act.
And I notice that Catholic businesses, which provide products or services to weddings, do not inquire about the engaged man and woman, to see if the business owner approves of the union. They still provide services to traditional weddings if the bride or groom is divorced and remarried, or if the couple have fallen away from the Catholic Church, or if the couple in some way believe or act contrary to Catholic teaching. No Catholic business refuses service to a traditional wedding, even if they are involved in some act that is gravely immoral under Catholic teaching. So there is no reason to single out same-sex weddings.
Certainly, under Catholic teaching, a true marriage is not possible between persons of the same gender. I don’t agree with the current socio-political trend toward legalization and cultural approval for same-sex marriages. But neither do I support treating anyone with contempt or denigration.
4. However, not everyone agrees with my assessment of the morality of providing goods and services to a same-sex wedding. And I don’t think that the government has any compelling interest in forcing businesses or individuals to participate materially in a religious ceremony against their conscience. In the current circumstances, a same-sex couple is able to find businesses willing to provide all of the products and services needed for their wedding. They are not harmed if the law permits businesses to decline to participate in a gay wedding. The wedding ceremony and to some extent the subsequent celebration of that wedding are religious in nature, and no one should be forced to participate in any religious service against their will. And if a wedding were held in an entirely secular non-religious manner, a business owner who nevertheless views weddings as a religious event should not be compelled to participate.
The law should very narrowly exempt businesses and individuals from being required to participate in any way in any religious event. But otherwise, businesses and individuals must provide their products and services to all. Such a law would permit an atheist to decline to provide food or flowers to a Catholic wedding. It would permit an orthodox Jewish business to decline to provide its services to a Muslim or Christian religious event.
5. Jesus ate and drank with tax collectors and sinners. Therefore, we Christians ought not to separate ourselves from others, on the basis of our understanding that their path in life is sinful. For there are many sinners among Christians, and no one proposes to refuse services to them.
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