Aleister Crowley's emphasis on the number 93 has always seemed
idiosyncratic to me -- we don't encounter much concerning 93 in
Kabbalistic texts before Crowley's time, no more than we find on
many other numbers. Numbers such as 36 and 72 are a great deal more
important in Kabbalah.

I suppose how we view 93 depends on how much importance we place in
the cult of Thelema, and how much credence we give Crowley as the
herald of a new aeon. My own view of Kabbalistic numerology is that
it is useful for stimulating connections between ideas, chains of
thought, and even on occasion for initiating insights, but that it
should not be raised to a level of importance that it does not
deserve. Crowley himself felt much the same way about it.

-Al-