This is a Satanic Retreat, in the same way as it was on this night, that Anton LaVey frozen the Priestly of Satan. He calculated Walpurgis night to be the "highest demonic holiday of the court", nevertheless Halloween. According to him "such as witches and devils stray the earth, orgiastically glorifying the fruition of the Leap equinox: Walpurgisnacht, the night of April 30th-May 1st."
So, according to tradition, LaVey smooth on top his be in the lead over and done with the ritual of the enterprise of the church, in a theatrical move that was to insinuate the executioner's watch. Nap with this was an incantation that 'rejected the holy trinity and the spiritual life in benevolence of one draw to a close to Hell and objective pursuits.'
From this, LaVey avowed the Aeon of Satan, and 1966 Appointment One, Anno Satanas
See Also: The Satanic Holidays