This is one of the most common misconceptions about Aleister Crowley. If by this question one means, did Crowley worship the being commonly known to Christians as Satan, the answer is an unequivocable no. Crowley's ideas of deity did not fit the typical mold; in his views, gods were symbolic of forces and powers to aid the spiritual explorer in his theurgic journey. Crowley at no time believed in a living demonic being deserving of worship. Crowley's religious practice, as it were, was inherently theurgic, dedicated solely to self discovery. Crowley espoused no dogma relating to god or gods and generally despised blind worship and dogmatic belief.

Was Crowley a Black Magician?

Certainly not. See above. Crowley's magick, as explored in voluminous writings, was centured on theurgic self discovery, self mastery, and experience of the divine. Crowley's "Law of Thelema" expressly forbids interference with the will of another, making black magick an impossibility. Said Crowley of Black magicians:

"To practice black magic you have to violate every principle of science, decency and intelligence . You must be obsessed with an insane idea of the importance of the petty object or your wretched and selfish desires ... I despise the thing to such an extent that I can hardly believe in the existence of people so debased and idiotic as to practise it."

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See also:

Crowley Gallery

Aleister Crowley Quotes