I was recently browsing an online Christian forum in which a poster asked, “Where does the Bible say marriage is only between one man and one woman?”
The answers were predictably depressing. As a bulk of Protestant denominations have accepted the LGBT movement, most of the respondents just flatly claimed that the Bible doesn’t restrict marriage to one man and one woman.
As Catholics, this might give us reason to be thankful for Sacred Tradition. Regardless of controversies on Biblical interpretation, we won’t face such drastic swings in sexual morality. Yet we should nonetheless be ready to face and refute such Protestant claims. Is it really the case that “biblical marriage”—between a man and a woman—isn’t actually all that biblical?
Indeed, there’s no single passage in the Bible that says, “Marriage is only between a man and a woman.” Of course, there is also no passage in the Bible that says, “Same-sex relationships are allowed and should be considered marriage.” Instead, these moral ideas are argued as conclusions from other, more explicit scriptural texts.
Even though the culturally relevant question is homosexuality, liberal Protestants often focus instead on another point of sexual ethics: polygamy, or having multiple wives at the same time. The Bible clearly records polygamous marriages—not just in Israel’s enemies, but even in the Patriarchs and revered kings of the chosen people. From this, some people will argue that biblical marriage is actually not between only one man and one woman, and if marriage can be between one man and multiple women, perhaps it can also be between two men or two women.
Even if the Bible endorses polygamy, this isn’t a valid argument for homosexuality. Polygamy is still a different kind of sexual union from same-sex relationships, and one doesn’t follow from the other. But does it?
Early parts of the Old Testament seem to. Many holy Israelites take multiple wives. Scripture records this historical fact without condemnation. Abraham, David, Solomon, Jacob—they are polygamous, and God and his prophets don’t speak out against their marital habits.
And not only are they silent, but at one point, Moses appears to command polygamy in the practice of Levirate marriage. Deuteronomy 25:5-10 outlines the practice: if two brothers live together and one dies without a son, the living brother should marry his brother’s widow and try to continue his family line. The living brother is not forced to do so, and the law does not specify whether he already has a wife of his own. But he’s strongly encouraged to marry the widow, and practically, the brother most often would’ve already been married—so, by implication, the law encourages polygamy.
Yet to conclude from this that Scripture endorses polygamy would be a flawed biblical interpretation. The Old Testament unfolded over thousands of years. Much changed over those millennia—in the secular structure of Israelite society, and also in its religious understanding and laws. God never contradicts himself, but he gradually revealed spiritual truth over many generations, culminating in his full self-revelation in his Son.
Jesus says as much in Matthew 19:8. God, through Moses, permitted Israelites to divorce in Deuteronomy 24; now Jesus, who is God, is banning divorce. But without contradiction—divorce was allowed as a concession to a people still spiritually immature, which permission now, in due time, is being revoked.
The Old Testament gives a similar principle. In Ezekiel 18:2-3, God forbids the proverb, “The parents have eaten sour grapes, and the children’s teeth are set on edge.” The proverb means that the children are being punished for the sins of their fathers. But such an idea comes from God’s earlier word—in Exodus 34:7, when God says the sins of the parents fall upon children down to three or four generations. God was forbidding something that he earlier seemed to imply.
Such things happen with all learning. We don’t teach kids fractions when they’re just learning to count. They’re not ready for it. When they are ready, we give them fractional math, and though it seems very different from the simple numbers we originally told them, we all know that this more advanced arithmetic doesn’t actually contradict our 123s and ABCs.
This takes us back to polygamy. Deuteronomy doesn’t explicitly endorse polygamy. It only implies it. And the later prophets show that such an implication is mistaken.
For one, though the Bible doesn’t say the Patriarchs’ polygamy is wrong, it shows it. Read about Abraham and Hagar, or David and Bathsheba, or Jacob and Leah. Again and again, kings and Patriarchs take multiple wives with disastrous consequences. We can read between the lines. Polygamy is shown to be a bad idea, even if it’s not said to be such.
Second, the prophets started using marital imagery to describe God and Israel. God is Israel’s husband. And he has only one chosen people. If God is not polygamous in such analogies, why should Israelites be?
Later Judaism thus started to have doubts about earlier polygamous allowances. By the return from their Babylonian exile, Jews had largely abandoned the practice. And by Rabbinical Judaism, polygamy was completely condemned.
We can go farther. Even if the Old Testament supports polygamy (as we’ve just shown, it doesn’t), the New Testament is what matters most for if its still allowable for us Christians. And plainly, the New Testament doesn’t allow it. Jesus says a man should be joined to his wife, and they will become one flesh (Matt. 19:3-6). Jesus defines adultery as even looking at another woman lustfully (5:27-28). And Paul commands that “each man should have his own wife and each woman her own husband” (1 Cor. 7:2).
A clear picture emerges. Marriage is between two people: one man, and one woman. Polygamy—whether tolerated or condemned in previous generations—is not part of God’s ultimate design.
This should be expected, because polygamy really works only in a culture of male dominion. It doesn’t work if a woman is supposed to be an equal and integral member of family and society, as the Bible clearly teaches. Whose in-laws do we see at Christmastime? Who gets priority when hubby is in the mood? How are the children raised with multiple, equal women acting as mom? How are decisions made? Things inevitably devolve into what actually happened in the Bible’s stories of polygamy: one wife playing second fiddle, one wife domineering, one set of children fading into the background, and one husband with a throbbing headache.
So we can confidently say that biblical marriage is between one man and one woman. Despite the controversy about the “man” and “woman” part of the definition, we need not question the word “one.” Polygamy was once tolerated in God’s plan, but it showed itself prone to domination and domestic strife. And so God’s people abandoned it, and Jesus condemned it. Frankly, I’m happy for that—and so is my wife.