Greek mythology, Iacchus.

In Greek mythology, Iacchus, is an epithet of Dionysus, particularly associated with the Mysteries at Eleusis, where he was considered to be the son of Zeus and Demeter. Iacchus was the torch bearer of the procession from Eleusinion to Eleusis on the sixth day of the greater mysteries, sometimes regarded as the herald of the 'divine child' of the Goddess, born in the underworld, and sometimes as the child itself. Iacchus was called "the light-bringing star of our nocturnal rite", giving him possible associations with Sirius and Sothis.