‘To become one flesh’ means much more than just the physical union. It means that two persons share everything they have, not only their bodies, not only their material possessions, but also their thinking and their feeling, their joy and their suffering, their hopes and their fears, their successes and their failures. ‘To become one flesh’ means that two persons become completely one with body, soul, and spirit, and yet there remains two different persons. This is the innermost mystery of marriage. It is hard to understand. Maybe we can’t understand it at all. We can only experience it.

-Trobisch, Walter, I Married You