Mark 10:8
And the two will become one flesh. So they are no longer two, but one flesh — the one flesh of Genesis 2:24 is the creation design for marriage: two persons becoming a new unity. The one flesh is not merely sexual union (though it includes it) but the comprehensive joining of two lives into a shared existence. So they are no longer two, but one flesh: the arithmetical impossibility is the theological reality — two remain two persons while becoming one flesh. The union is real, not metaphorical.