The article analyses the vision of the devil in the selected tales of the Vie des peres, a collection of pious tales from the thirteenth century, freely inspired by patristic literature and medieval exempla. The period in which the collection was written, the thirteenth century, bridges the gap between the early and late Middle Ages: it is a time when the perception of the devil is changing, and he is becoming increasingly feared. The analysis focuses mainly on four stories in which the devil is at the centre of the story, and in which his very image is a source of fear and a key element of the story: 'Devil's Mouth', 'Devils Vision' and two versions of 'Devil's Image'. The vision of the devil in these stories coincides with the teratological vision that is dominant in the iconography, to which the stories directly allude. The message of these stories is generally positive: the protagonists almost always manage to overcome their fears and free themselves from the power of the devil. In this way, the authors avoid the trap of Manichaeism: the devil, despite his cunning and sophistication, is in the end only a caricature of an angel, unable to oppose God effectively. The fear of the devil appears several times on the pages of Vie des peres, but it is the message of hope that dominates.