His constant and successful researches in Roman archives won him the friendship of Cardinal Baronius, through whom he was made titular Abbot of San Baronzio in the Diocese of Pistoia, and custodian of the Vatican Library.

He was persuaded that St. Gregory the Great was a genuine disciple of St. Benedict, and wrote in defense of this thesis De S. Gregorii monachatu benedictino libri duo (Salzburg, 1620).

[2] His ardor for the glory of the Benedictine Order troubled his judgment occasionally, says Father Hurter, e.g. when he claimed for it such persons as St. Columbanus of Bobbio, St. Thomas Aquinas, St. Francis of Assisi, St. Ignatius Loyola.

He inaugurated the controversy concerning the authorship of the work known as the Spiritual Exercises of St. Ignatius by his book De religiosâ S. Ignatii, sive S. Enneconis fundatoris soc.

He had long hoped to found at Rome a Collegium Gregorianum de propagandâ fide, in which young Benedictines might be trained for foreign missions, after the spirit and teachings of St. Gregory the Great, Apostle of the Anglo-Saxons.