This image and likeness of God, which is essential for the human being, is passed on by the man and woman, as spouses and parents, to their descendants: “Be fruitful and multiply, and fill the earth and subdue it” (Gen 1: 28). The Creator entrusts dominion over the earth to the human race, to all persons, to all men and women, who derive their dignity and vocation from the common “beginning”.
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From the very beginning they appear as a “unity of the two”, and this signifies that the original solitude is overcome, the solitude in which man does not find “a helper fit for him” (Gen 2:20). Is it only a question here of a “helper” in activity, in “subduing the earth” (cf. Gen 1: 28)? Certainly it is a matter of a life’s companion, with whom, as a wife, the man can unite himself, becoming with her “one flesh” and for this reason leaving “his father and his mother” (cf. Gen 2: 24). Thus in the same context as the creation of man and woman, the biblical account speaks of God’s instituting marriage as an indispensable condition for the transmission of life to new generations, the transmission of life to which marriage and conjugal love are by their nature ordered: “Be fruitful and multiply, and fill the earth and subdue it” (Gen 1:28).