Pope Francis, addressing the Polish Jesuits in Crakow, said: “Today the Church needs to grow in discernment, in the ability to discern. And priests, above all, really need it for their ministry. This is why we need to teach it to seminarians and priests in formation: they are the ones usually entrusted with the confidences of the conscience of the faithful. Spiritual direction is not solely a priestly charism, but also lay, it is true. But, I repeat, you must teach this above all to priests, helping them in the light of the Exercises in the dynamic of pastoral discernment, which respects the law but knows how to go beyond. .. We need to truly understand this: in life not all is black on white or white on black. No! The shades of grey prevail in life. We must teach them to discern in this grey area.” Following this invitation of our Pope Francis, we shall consider here the spiritual journey of Peter the Apostle in his following of Jesus of Nazareth: the process of discerning spirit.