John lived after the Protestant Reformation and the Council of Trent. He and his followers projected a new congregation of diocesan priests. For some reason the plan, which was ultimately approved, provoked great political opposition. John was exiled from his home town of Lucca, Italy, for almost the entire remainder of his life. He received encouragement and help from Saint Philip Neri, who gave him his lodgings—along with the care of his cat!
In 1579, John formed the Confraternity of Christian Doctrine, and published a compendium of Christian doctrine that remained in use until the 19th century.
Father Leonardi and his priests became a great power for good in Italy, and their congregation was confirmed by Pope Clement in 1595. John died at the age of 68 from a disease caught when tending those stricken by the plague.
By the deliberate policy of the founder, the Clerks Regular of the Mother of God have never had more than 15 churches, and today form only a very small congregation. The liturgical feast of Saint John Leonardi is celebrated on October 9.
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