Ephesians 5:31

31.For this cause. This is an exact quotation from the writings of Moses. (Genesis 2:24.) And what does it mean? As Eve was formed out of the substance of her husband, and thus was a part of himself; so, if we are the true members of Christ, we share his substance, and by this intercourse unite into one body. In short, Paul describes our union to Christ, a symbol and pledge of which is given to us in the ordinance of the supper. Those who talk about the torture exercised on this passage to make it refer to the Lord’s supper, while no mention is made of the supper, but of marriage, are egregiously mistaken. When they admit that the death of Christ is commemorated in the supper, but not that such intercourse exists as we assert from the words of Christ, we quote this passage against them. Paul says that we are members of his flesh and of his bones. Do we wonder then, that in the Lord’s supper he holds out his body to be enjoyed by us, and to nourish us unto eternal life? Thus we prove that the only union which we maintain to be represented by the Lord’s supper is here declared in its truth and consequences by the apostle.

Two subjects are exhibited together; for the spiritual union between Christ and his church is so treated as to illustrate the common law of marriage, to which the quotation from Moses relates. He immediately adds, that the saying is fulfilled in Christ and the church. Every opportunity which presents itself for proclaiming our obligations to Christ is readily embraced, but he adapts his illustration of them to the present subject. It is uncertain whether Moses introduces Adam as using these words, or gives them as an inference drawn by himself from the creation of man. Nor is it of much consequence which of these views be taken; for, in either case, we must hold it to be an announcement of the will of God, enjoining the duties which men owe to their wives.

He shall leave his father and mother. As if he had said, “Let him rather leave his father and mother than not cleave to his wife.” The marriage bond does not set aside the other duties of mankind, nor are the commandments of God so inconsistent with each other, that a man cannot be a good and faithful husband without ceasing to be a dutiful son. It is altogether a question of degree. Moses draws the comparison, in order to express more strongly the close and sacred union which subsists between husband and wife. A son is bound by an inviolable law of nature to perform his duties towards his father; and when the obligations of a husband towards his wife are declared to be stronger, their force is the better understood. He who resolves to be a good husband will not fail to perform his filial duties, but will regard marriage as more sacred than all other ties.

And they two shall be one flesh. They shall be one man, or, to use a common phrase, they shall constitute one person; which certainly would not hold true with regard to any other kind of relationship. All depends on this, that the wife was formed of the flesh and bones of her husband. Such is the union between us and Christ, who in some sort makes us partakers of his substance. “We are bone of his bone, and flesh of his flesh,” (Genesis 2:23;) not because, like ourselves, he has a human nature, but because, by the power of his Spirit, he makes us a part of his body, so that from him we derive our life.