Why does the Catholic Church oppose gay marriage?
Because for the Church, the issue isn’t just with homosexuality – it’s also with marriage. For the Church, one of the two integral aspects of marriage is its fecundity. Conjugal love “stands under a twofold obligation of fidelity and fecundity,” (Catechism of the Catholic Church 2363). A homosexual marriage cannot be fruitful, it is not in the order of natural law, therefore there can be no such thing as a homosexual marriage. With regard to homosexual relations (within or not within a marriage): “They are contrary to the natural law. They close the sexual act to the gift of life. They do not proceed from a genuine affective and sexual complementarity,” (CCC 2357). “The spouses’ union achieves the twofold end of marriage: the good of the spouses themselves and the transmission of life. These two meanings or values of marriage cannot be separated without altering the couple’s spiritual life and compromising the goods of marriage and the future of the family,” (CCC 2363).
