Demon Vassago is described in several old Grimoires: The book of Oberon, Book of Incantations, Goetia and some other old Occult sources.
Below you will find a small mix of information about Vassago that will help you to summon this demon.
Demon Vassago: Goetia
Demon Vassago is the third spirit. This spirit is of a good nature, and he can tell you about things concerning the past and the future, and he can also discover all things hidden or lost.
Vassago rules over 26 legions of spirits.
Demon Vassago: Daemonolatry Goetia
If you suspect that you are under a curse, then you might want to summon Vassago, because he will tell you the truth. This spirit can also give you advice when you are dealing with difficult people.
Source: Goetia & Daemonolatry Goetia by S. Connolly
A similar demon
If you want to know if an enemy has cursed you, then you might want to summon Malphas from Goetia. Malphas does his job very nicely and he can also protect you.
Vassago: when to summon him?
Vassago belongs to the Goetia group of Princes and Prelates. This group of spirits is matched to Qlipha Gamchicoth on the Qliphotic Tree. Note, that the chart you see above is based on the information found in the Clavicula Salomonis.
If you know the Tree of Life, then Vassago comes from Chesed. I use the correspondences of Chesed even for Gamchicoth.
Ruling planet: Jupiter
Astrological hour: Jupiter
Paper seal colour: blue
Gems: sapphire & amethyst
Number: 4 (4 blue candles for example)
Plant: olive (use olive oil)
Scent: cedar (I use cinnamon)
Well, the best day to summon Vassago is a Thursday. You can fine tune your magick by doing it during the astrological hour of Jupiter.
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