- Nine Muses.
- Nine choirs of angels. (http://www.religionfacts.com/christianity/symbols/numbers.htm)
- "Number of the patience, the meditation."
- "Number of the harmony, it represents the inspiration and the perfection of the ideas."
- "Nine is the number of the one who accomplishes the divine will. According to the Cabal, it is also the number of the achievement."
- "Being the last simple number, it is the number of finalization or finition; it is therefore the most complex, that marks the full lighting up of the numerical series."
- "As a product of 3 x 3, it is the expression of the perfection." -- http://www.ridingthebeast.com/numbers/nu9.php