Pope Francis was trained in the school of Saint Ignatius' Spiritual Exercises. This article develops the roots of this spiritual learning and the infuence of leading teachers (such as Hugo Rahner, Miguel A. Fiorito, Gaston Fessard) in the interpretation of the charism of the Society of Jesus: magis, discernment, charitas discreta, spiritual combat, dialectic inscribed in the adage Non coerceri maximo, contineri tamen a minimo divinum est. The author examines the text of the Spiritual Exercices Jorge M. Bergoglio offered the Spanish bishops (2006) and the Pope's Exhortation on Holiness Gaudete et exsultate. In this way, this study shows that Ignatian spirituality is a hallmark of Francis' pontificate: so discernment an instrument for government and an aid on the path of holiness to follow the Lord more closely in the spiritual combat of faith under the cross of Christ.