"They have philosophers and theologians who are held in much honour and are called Druids. It is a custom of the Gauls that no one performs a sacrifice without the assistance of a philosopher, for they say that offerings to the gods ought only to be made through the mediation of these men, who are learned in the divine nature and, so to speak, familiar with it, and it is through their agency that the blessings of the gods should properly be sought."
Diodorus Siculus, Histories, V, 31, 1st century BCE
If the role of the bard is to listen to, learn about, speak and sing of spiritual realms and their inhabitants, and that of the ovate is to see them, then the role of the Druid is to enter into those worlds and meet directly with the spirits who inhabit them; spirits of nature, the ancestors, and the gods. The Druid is the walker between worlds, the shaman, shape-shifter, priest, teacher and sage of our tradition