As reported in several sources, former Veep Joe Biden officiated at a same-sex marriage ceremony this past weekend. In 2016, Biden also officiated at a gay marriage. On both occasions, Biden had the role usually fulfilled by a priest or minister, in other words, he actually pronounced the couple married. He was not merely attending the wedding, nor merely in the wedding party.
A faithful Catholic might morally attend a wedding ceremony. Such attendance does not imply approval for same-sex marriages. A wedding of friends or family could be attended, despite the person’s belief in Catholic teaching, if the good consequences outweigh the bad, and if the Catholic has only good intentions. Merely attending a ceremony does not imply belief in the heresy that a valid marriage is possible between two persons of the same sex.
However, officiating at a gay marriage is in a different category. Biden voluntarily took the role of celebrant of the marriage, and in doing so expresses his belief that gay marriage is a valid type of marriage. He was not a government official required to issue marriage licenses to all who apply, nor a judge required to officiate for all who apply, for a marriage. He chose to express his adherence to an idea condemned by the Bible and the Church.
Dr. Ed Peters wrote a post on a previous Biden gay marriage ceremony. Peters is of the view that infallible teachings are divided into two types, and that one only commits heresy by sinning against an infallible teaching of one type, those that are divinely-revealed, as opposed to the other type, those that are to be held definitively.
I disagree with this distinction, as I explain in this post. The majority of magisterial teachings on the subject weigh heavily in favor of only two types of teaching, infallible and non-infallible, without any further division of infallible teachings.
In any case, that a valid marriage is between man and woman is divinely-revealed in Sacred Scripture and Sacred Tradition, and is infallibly taught by the ordinary and universal Magisterium. So the deed of Biden in officiating at a same-sex marriage, and his public statements on gay rights and gay marriage, make it clear that he is guilty of heresy and grave scandal in this matter. He is automatically excommunicated (latae sententiae) due to the sin of heresy.
And for the sake of the faithful, he should be excommunicated by a judgment and declaration of Church authority (ferendae sententiae). But the Bishops and Cardinals have not shown themselves willing to excommunicate Catholic politicians, even when they openly reject the teaching of Christ and His Church.
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