Friends, in today’s Gospel from the Sermon on the Mount, the Lord prohibits divorce.
Is there any better description of sex anywhere in the literature of the world than that provocative line, “The two of them become one flesh?” In a Jewish context, flesh carries the sense of the whole person. Hence sexual union is meant to be a union at all levels.
A husband says to his wife, “My life is no longer about me; it’s about you and the children we will have.” And the wife says the same thing to her husband: “My life is not mine anymore; it belongs to you and our children.”
Some might expect Jesus to have a soft or relativized teaching on divorce, but later in Matthew’s Gospel he firmly declares: “What God has joined together, no human being must separate.” The husband and wife, who become one flesh, are brought together, not just by their mutual attraction, but by God. Their union is ingredient in God’s purposes. And this is why it cannot be undone. God doesn’t go back on his word.