And Sarai Abram's wife took Hagar her maid the Egyptian, after Abram had dwelt ten years in the land of Canaan, and gave her to her husband Abram to be his wife.
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Ambrose of Milan
AD 397
It was not because he was ablaze with the heat of some unbridled passion, not because he was overcome by the charm of seductive beauty that Abraham gave preference to a relationship with a slave girl over the conjugal bed, but through a desire to procure a posterity and to enlarge his progeny. After the flood the human race was still numerically sparse. Hence it was also a matter of moral obligation that no one be seen to have failed to render the debt to nature. For this reason, even the children of holy Lot were inspired by this motive to procure a posterity for themselves so that the human race would not become extinct. Thus the merit of having done one’s duty to society excused individual guilt. And it is not without significance that the wife is presented as the instigator of the deed. In [a] sense [this] exculpates her husband, so that no one could believe that he was carried away by some mad perversion. At the same time … women might learn to love their husbands, not to allow themselves to be tormented by empty suspicions of infidelity and not to dislike their stepchildren, when they themselves have been childless. That wonderful wife desired only that her husband forgive her sterility, and, wishing to avoid being herself the reason for her husband’s not having children, she persuades him to go in to the slave girl. Later on, Leah and Rachel did the same thing. Learn, O woman, to put aside jealousy, which often drives women to madness. .