Every faithful Roman Catholic must believe the teaching of the Church on matters of faith, morals, and salvation. The infallible teachings of the Magisterium require the full assent of faith, and obstinate denial or obstinate doubt of any infallible magisterial teaching is the grave sin of heresy. A person cannot be a full and faithful member of the Church while rejecting Her definitive and irreformable teachings. And these teachings are certain to be true because the Church is the Body of Christ, guided by the Holy Spirit. These infallible teachings are truly the teachings of Jesus Christ.
The non-infallible teachings of the Roman Catholic Magisterium require religious assent, not the full assent of faith, and so doubt or denial of some few non-infallible teachings is not heresy and might not be a grave sin. The non-infallible teachings allow for a limited possibility of faithful dissent, because these teachings are subject to a limited possibility of error. But even a non-infallible teaching cannot err to such an extent as to lead the faithful away from the path of salvation.
By the ordinary and universal Magisterium, the Catholic Church infallibly teaches that the Christian Sacrament of marriage can only exist between one man and one woman. So a same-sex marriage can never be the true Sacrament of marriage. Now some few natural marriages during Old Testament times were polygamous, but these marriages were not a sacrament and were always heterosexual.
Moreover, the Church teaches that certain types of sexual acts are intrinsically evil and always gravely immoral, including all sexual acts outside of a true marriage and all unnatural sexual acts. All extra-marital sexual acts are gravely immoral. All unnatural sexual acts, even between a husband and wife, are gravely immoral. These gravely immoral acts are contrary to the eternal moral law, and that law applies to all human persons, regardless of religion, sexual orientation, or other factors.
Pope Saint John Paul II: “No circumstance, no purpose, no law whatsoever can ever make licit an act which is intrinsically illicit, since it is contrary to the Law of God which is written in every human heart, knowable by reason itself, and proclaimed by the Church.” [Evangelium Vitae 64].
The cultural and legal approval of same-sex marriage ignores both the Christian definition of a true marriage, taught by Jesus Christ (Mt 19:4-6), and the condemnation of unnatural sexual acts by the eternal moral law and the Church. Approval for gay marriage implies approval for unnatural sexual acts. The claim of “marriage equality” implies that all sexual acts are equal as to their morality.
The widespread view among Christians that homosexual relationships are good and that same-sex marriage is no different from traditional marriage is based largely on the erosion and collapse of Christian sexual ethics. The vast majority of Christians, Catholic Christians, and even Mass-going Catholics commit grave sexual sins without repentance. Most Catholics no longer go to Confession at all. Most Catholics and most non-Catholic Christians exempt anything pertaining to sex from conscience and morality.
Of course a Catholic who is unrepentant from his or her own grave sexual sins (e.g. pornography, masturbation, pre-marital sex, unnatural sexual acts within marriage) will refuse to condemn the unnatural sexual acts of same-sex marriage. A vote against same-sex marriage is an acknowledgement that certain types of sexual acts are gravely immoral; for many Catholics, such a vote would be a self-condemnation. For if they have never committed homosexual acts, they have committed other grave sexual sins and they are unrepentant. It is easier to pretend that all sexual acts are moral than to examine one’s own conscience, repent, and confess.
It is not sufficient for the Pope and the Bishops to convince Catholics to accept the Christian definition of marriage as between one man and one woman. They must also convince Catholics to accept Church teaching on sexual ethics, to reject all gravely immoral sexual acts, and to live a chaste life. Only then will Catholics oppose the legalization of same-sex marriage as well as the cultural normalization of gravely immoral sexual acts of every type.
For a married person, chastity requires refraining from all sexual acts, other than natural marital relations open to life. For a single person, chastity requires refraining from all sexual acts. But single persons are not properly called celibate. Celibacy is a renunciation of marriage as well as all sexual acts, usually by a vow or formal promise to the Church.
Arguments and Replies
1. Argument: marriage is merely the union of any two loving persons
Reply: Every good human person loves many different persons: friends, relatives, neighbors, co-workers, persons in need, etc. The mere fact that two persons love each other does not a marriage make. Marriage implies a sexual relationship between two persons. Approval by society for traditional marriage implies that natural marital relations is moral. But if society approves of gay marriage, this implies approval of unnatural sexual acts.
2. Argument: legalization of same-sex marriage is marriage equality.
Reply: The laws of society permit killing in self-defense, but condemn murder. Not all acts of killing are morally equal, and so they are not treated equally by the law. The laws of society permit verbal expressions of disagreement, but condemn verbal threats of violence. Not all verbal expressions are morally equal, and so they are not treated equally by the law. Human law cannot ignore the eternal moral law. Gravely immoral acts cannot be treated by the law as if they were the same as moral acts. Same-sex marriage is not the same as traditional marriage because unnatural sexual acts are gravely immoral, whereas natural marital relations is moral. Same-sex marriage cannot be equal to traditional marriage because unnatural sexual acts are intrinsically evil and always gravely immoral.
3. Argument: opposition to legalized gay marriage is a type of unjust discrimination, since homosexuals would be denied marriage otherwise.
Reply: Any individual sins gravely if he or she commits any gravely immoral sexual act. A man and woman sin gravely if they have sexual relations outside of marriage. Approval for same-sex marriage implies approval for acts gravely contrary to the eternal moral law, which binds all human persons regardless of religion or sexual orientation. It is not unjust nor discriminatory to decline to give social or legal approval to gravely immoral sexual acts. The demand for social and legal approval of same-sex marriage is essentially a demand to approve of grave sexual sins. But since the eternal moral law binds all human persons, the distinction between moral and immoral sexual acts is not a type of unjust discrimination.
4. Argument: the government has no right to judge or condemn sexual acts between two consenting adults
Reply: Human law is always ultimately based on morality. Even the pro-gay marriage arguments are essentially (misguided) moral arguments, since they are predicated on fairness and justice, which are moral terms. Now not every gravely immoral act must be made illegal under human law. But this principle cannot be used to justify formal legal approval for gravely immoral acts. Human law should never give formal approval to any grave sin, even if that sin is not made illegal in a pluralistic society.
5. Argument: opposition to same-sex marriage is intolerance or hatred or bigotry
Reply: A difference of opinion on social and political issues is to be expected in a pluralistic society. The pressure on Christians to adhere to this new view of marriage is itself intolerant and even totalitarian: no disagreement is tolerated, even when based on religious or moral beliefs. Our political system is democratic and our cultural system is totalitarian.
But for the Christian faithful, opposition to gay marriage is not based on a rejection of human persons via hate or bias, but rather on faith in the teachings of the Bible and the Church. The opposition to gravely immoral acts by Christians is a rejection of certain types of acts, not a rejection of persons.
6. Argument: Christians who oppose gay marriage are attempting to impose their morality on others
Reply: The pro-gay marriage side argues based on concepts of fairness and justice, that is to say, based on morality. The Christian faithful simply disagree with that assessment of what constitutes justice and fairness in the realm of marriage. We should be free to express our ideas and to vote our consciences, just as the other side is free to do.
On the other hand, the culture (and perhaps soon the law) is attempting to impose a disordered understanding of morality and marriage on the Christian faithful, depriving us of our right to freedom of speech and religion. The pro-gay marriage side has been making unjust accusations against all who oppose their view: accusations of hatred, bigotry, homophobia, etc. And this rhetoric is accompanied by threats to shut down businesses or pressure individuals to be fired, via boycotts and protests, and to enact laws putting Christians in prison for refusing to comply with this disordered understanding.
Society and law should always distinguish between moral acts and gravely immoral acts. The legalization of same-sex marriage portrays gravely immoral sexual acts as if they were equal to moral sexual acts. The societal approval for same-sex relationships, with or without a legal marriage, implies a rejection of sexual morality.
Why is there so much support among straight Christian voters for legalized same-sex marriage? It is because these Christians have long ago abandoned traditional Christian teaching on sexual ethics. Without sexual ethics, marriage becomes a mere legal construct, within no inherent moral meaning. Legalized gay marriage is simply the next step in the rejection of traditional sexual ethics by Christians.
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