The Mortara case refers to Pope Pius IX's 1858 removal of a six-year-old Jewish boy, Edgardo Mortara, from his parents in Bologna, Italy. Six years after Edgardo was born, it was reported that the family's Christian housekeeper had baptized the boy after he had fallen ill as an infant and was allegedly in danger of death. Since canon law and civil law stipulated that a baptized child must be raised Catholic, Pius IX used his power as head of the papal states to remove the boy.

In advocating for the return of the child, the Mortara's submitted to the Vatican a two-part document, which appealed to the teachings of Thomas Aquinas against baptism of Jewish children invitis parentibus (against the will of the parents). The papal counsel's reply denied the request, citing Aquinas's teaching to argue that Edgardo's baptism was valid, and that he belonged to the Church. Today, some Catholic theologians defend or at least excuse the Pope's decision with appeal to the works of Aquinas. Which side had the correct interpretation of Aquinas's teaching? And how does this answer impact Catholic theology and Catholic Jewish-relations today?

The Mortara Case and St. Thomas Aquinas's Defense of Jewish Parental Authority adjudicates the claims of both sides of the debate through an analysis of Aquinas's teaching as it is interpreted in the Italian and Latin original documents from the 1858 case, which are housed in the Vatican Apostolic Archives, and reproduced here, with facing English translations, for the first time. Tapie demonstrates that, for Aquinas, Jewish parental rights are an order of the natural law, which Aquinas likened to a spiritualis uterus (spiritual womb). Through the metaphor of the spiritual womb, Aquinas merged the Roman institution of parental rights with the theological concept of the natural law. Tapie concludes by examining baptism invitis parentibus in the current Code of Canon Law with attention to the Second Vatican Council's teaching on religious freedom and the Jewish people.