Augustine:
That the holy fathers of olden times after Abraham, and before him, to whom God gave His testimony that “they pleased Him,” [Heb. 11:4-6] thus used their wives, no one who is a Christian ought to doubt, since it was permitted to certain individuals amongst them to have a plurality of wives, where the reason was for the multiplication of their offspring, not the desire of varying gratification… . . That the good purpose of marriage, however, is better promoted by one husband with one wife, than by a husband with several wives, is shown plainly enough by the very first union of a married pair, which was made by the Divine Being Himself, with the intention of marriages taking their beginning therefrom, and of its affording to them a more honourable precedent. In the advance, however, of the human race, it came to pass that to certain good men were united a plurality of good wives, — many to each; and from this it would seem that moderation sought rather unity on one side for dignity, while nature permitted plurality on the other side for fecundity. For on natural principles it is more feasible for one to have dominion over many, than for many to have dominion over one………** Now, although the fact of the matter is, that while nature loves singleness in her dominations, but we may see plurality existing more readily in the subordinate portion of our race; yet for all that, it was at no time lawful for one man to have a plurality of wives, except for the purpose of a greater number of children springing from him. Wherefore, if one woman cohabits with several men, inasmuch as no increase of offspring accrues to her there from, but only a more frequent gratification of lust, she cannot possibly be a wife, but only a harlot………For this is preserved in the case of Christ and the Church; so that, as a living one with a living one, there is no divorce, no separation forever. And so complete is the observance of this bond in the city of our God, in His holy mountain—that is to say, in the Church of Christ—by all married believers, who are undoubtedly members of Christ, that, although women marry, and men take wives, for the purpose of procreating children, it is never permitted one to put away even an unfruitful wife for the sake of having another to bear children…** (A Select Library of the Nicene and Post-Nicene Fathers of The Christian Church, Volume 5, page 267).
According to Augustine it seems one man and one woman is the best marriage; and all marriages are for procreation. Same-sex unions do not procreate.
Others never had a good math teacher…still doesn’t make 2+2=5.