Why do we who identify as conservative evangelicals put so much emphasis on the importance of heterosexual monogamy as the only morally acceptable option? Two reasons may be cited. Of course, I could mention historical, social, and cultural arguments, even psychological arguments for the benefits and blessings of heterosexual marriage. But let me mention two biblical arguments, both of which were recently discussed by my friend Ray Ortlund.
First, this is God’s will for all mankind! Moses said it clearly: “Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh” (Genesis 2:24). In a world where the primary human relationship was of a child and his parents, this was a stunning statement. We are being told that nothing trumps the one-flesh relationship between a man and his wife. A person’s deepest and most abiding loyalty is to his/her spouse.
A man is to “hold fast” or “cleave” to his wife. I love how Ray put it: “A man, in marrying,” said Ray, “enfolds his wife into his heart. He rejoices to identify with her: ‘This at last is bone of my bones and flesh of my flesh’ (verse 23). At every level of his being, he becomes wholeheartedly devoted to her, as to no other.”
And the two shall become “one flesh.” Says Ortlund, “It means, one mortal life fully shared. Two selfish me’s start learning to think like one unified us, sharing one everything: one life, one reputation, one bed, one suffering, one budget, one family, one mission, and so forth. No barriers. No hiding. No aloofness. Now total openness with total sharing and total solidarity, until death parts them.”
To reinforce this truth Jesus declared that it was God who has joined or united them in this way (Matt. 19:6). “What we see then, is that marriage is not a product of human social evolution; marriage came down from God. And he defined it for us. He has the right to. It belongs to him” (Ortlund).
Second, when the Apostle Paul picks up on this in Ephesians 5 he states it with even greater clarity: “We are members of his [Christ’s] body. ‘Therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh’” (Ephesians 5:30-31).
Notice his logic. “We are members of Christ’s body. He loved us. He chose us. He gave himself up for us. He will present us someday in splendor. We are united with Christ now and forever. Therefore, our union with Christ is the reason why, a man and woman get married and live united as ‘one flesh.’ Human marriages are miniature social platforms on which the gospel is to be displayed. . . . Marriage is a gospel issue. That is why clarity about its definition matters to Christians. If we depart from, or fail to stand up for, the biblical view of marriage, we are taking a step away from the gospel itself. The whole Bible is the story of the marital love of God. Our whole lives are that story, if we have eyes to see” (Ortlund).