by dorje on Tue Feb 02, 2010
The number 108 predates Buddhism. The reason why the theme of 108 continues in Buddhism is basically it was a convenient assimilation tool from Hinduism, where numerology, astrology, and so on were plentiful. And as we all know, Buddhism originated from India, where Hinduism originated as well. So it was a cultural thingy, no mysticism there.
The later Mahayanist, and especially the Vajrayanist, movements might have incorporated it even more through the incorporation of rituals and tantra. Still, there is not much mysticism, because they are used as a convenient mnemonic.