In biblical texts, the desert is used as a means to test faith: lacking water but full of monsters, dangers, and temptations. The iconography of the desert gained popularity at the end of the Middle Ages. The origin of this success can be explained by the rise of the saints' cults, like Saints Anthony, Paul, and Jerome. The article shows that the more the paintings represented realistic landscapes during the fifteenth century, the more the desert attributes became symbolic, leading to the paradox of a forest representing a desert landscape.