Actually, the expansion of “marriage” beyond the classical meaning shared alike by Jews, Christians, Buddhists, pretty much all pagans (yes, even those who were into buggery as a pastime were scandalized by Nero “marrying” a eunuch), is one of the few things that the left fancies to be mercies Jesus would approve of that we can be absolutely certain on the basis of the plain words of Scripture that He would not approve: Our Lord’s comments on marriage are grounded in biology — “But from the beginning of the creation God made them male and female. For this cause shall a man leave his father and mother, and cleave to his wife; And they twain shall be one flesh: so then they are no more twain, but one flesh. What therefore God hath joined together, let not man put asunder.”
Man and wife was not just a practical arrangement, it was a symbolic one.
The glee of buggery is a sort of idolatry. And it is sad.