9 It is not surprising, then, that this athlete of Jesus Christ, adorned with these gifts of grace, should have achieved such notable progress in the apostolic field, and been able to gather rich fruits in the saving of souls. He was on fire to preserve, extend, and defend the Catholic faith. Thus, when serving as a teacher at Vilna, and later when living in other cities, he diligently taught the elements of Christian doctrine, and encouraged devotion to the Eucharist, and an ardent and filial love of the Virgin Mother of God.
Source: Invicti Athletae (Vatican.va)