The relationship of Apollo with the Underworld was an obscure one. This god was more closely connected with the luminous firmament and the purifications achieved through Fire. In the Homeric age Apollo was supposed to have demanded through his Delphic oracle certain human sacrifices.This contradiction can however be explained by an old relation of Apollo with Leto, Artemis and Dionysos, that was transformed to a cult with a dual character: of a luminous and at the same time of a mystic and chthonian nature.