Gregory of Nyssa, Lettre canonique. Lettre sur la Pythonisse et autres lettres pastorales. Introduction, translation and notes by Pierre Maraval, « Sources chrétiennes » #588, Paris, Éditions du Cerf, 2017, 290 p. Pierre Maraval, to whom the collection « Sources chrétiennes » already owes several volumes by St. Gregory of Nyssa, gathered here several works by the great Cappadocian father. They are quite different in nature, but all deal with pastoral care. The first work