Stephen B. Clark commenting on Genesis 2:14.
“While it would be a mistake to regard one flesh solely in terms of sexual intercourse, it would be an even greater mistake to miss the reference to family and reproduction and concentrate instead on the modern idea of companionship. One reason that animals will not do as a partner for man is their inadequacy for reproductive purposes. The man needs someone with whom he can live and establish a household. Implicit in this, especially for the first man, is the need for sexual relations and reproduction.”
Once we make reproduction an option in marriage instead of a normal requirement and expectation we remove one of the impediments to gay marriage. If siring and birthing children is a central part of the marriage relationship then gay marriage makes no sense. Sodomites and lesbians cannot do this. But if the marriage relationship is based primarily or solely on companionship, love, mutual affection for and interest in one another then why can two men or two women or three men with five women or a man and dog not get married? Once again we are reminded that how we interpret Genesis 1-3 will often set a trajectory for how we view the rest of the Scriptures, the world, man, and fundamental institutions, such as marriage.
There are many reasons gay marriage has become normal in our society. But the failure of Christians to see bearing children as an essential part of marriage has been a contributing factor.
By the way, I am not saying a couple who cannot bear children has a deficient marriage. Note my phrase “normal requirement and expectation.” There are exceptions, but the norm for a married couple should be reproduction.