In his Sententiarum libri IV (Four Books of Sentences, 1148-1151), Peter Lombard defined a wife's place in Christian marriage

1 Why woman was formed from the side of man Now, because she was not given as a servant or mistress, therefore, in the beginning she was neither formed from the highest nor the lowest, but from the side of man on account of the conjugal partnership If she had been made from the highest, that is from the head, she would seem to have been created for domination But if from the lowest, that is from the feet, it would seem that she ought to be subjected to servitude But because she was intended neither as a mistress nor as a servant, she was created from the middle, that is the side, because she was intended for conjugal partnership

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