If he shares with the lion or the eagle the position of emblematic figure almost universal, the deer has an almost unique feature which is to serve as a courier. Great communicant, the deer is a familiar of the celestial spheres of which it ensures the link, in both directions. It also has access to the underground world, present in Celtic legends as in Siberian shamanism: its woods draw the card of access to the invisible world. Thus, by its woods that grow (born) and fall (die) every year, he incarnates spiritual death followed by a rebirth.This book shows that the deer occupies a notable place in the Christian and Sufi hagiographies.Thierry Zarcone works in CNRS as a researcher. His research focuses on intellectual and religious history in the Turkish and Iranian worlds. He is also a consultant to the l’Office for Democratic Institutions and Human Rights, an organism of OCDE.Jean-Pierre Laurant is a Historian. Specialist of René Guénon and christian esoterism on XIXth and XXth centuries in France.