What is the Tight-Fillet Spell for Sun Wukong’s Headband?
Edit: I’ve whipped up an article on my research blog:
https://journeytothewestresearch.com/2022/01/23/the-tightening-spell-of-sun-wukongs-golden-headband/
Here's a fun thought experiment: What is the tightening spell (jingu zhou, 緊箍咒) for Sun Wukong's golden headband? Journey to the West (Xiyouji, 西遊記, 1592) never mentions it. But I'd like to suggest a mantra based on historical religious beliefs and iconography. Come with me on a brief journey...
As previously noted, the fillet is based on a ritual headband worn by Buddhist yogins in ancient India. The Hevajra Tanta (Dabei kongzhi jingang dajiao wang yigui jing, 大悲空智金剛大教王儀軌經, 8th-c.) states it symbolizes the Buddha Akshobhya (Ch: Achu, 阿閦; Budong, 不動), who gained enlightenment through moralistic practices of right speech and action.
Akshobhya and the other Wisdom Buddhas are sometimes depicted as small figures or colored jewels in the headdress of the Manjusri Bodhisattva. (This might suggest a religiously accurate version of Monkey's band would also include a medallion of the buddha).
Therefore, given the connection to Akshobhya, I'd like to suggest the tightening spell for Monkey’s headband—within the context of our thought experiment—is the buddha's mantra: Oṃ a kṣo bhya hūṃ.
The monk Tripitaka would recite Akshobhya's mantra to activate the tightening spell, thus reminding Sun Wukong of right speech and action—i.e. "Stop murdering everyone within your reach!"
There's a longer chant associated with the buddha called the "Mantra of Akshobhya" (Achu fo xinzhou, 阿閦佛心咒). It was apparently translated by the historical Xuanzang (on whom Tripitaka is based). I'll leave it up to you which one you like better. https://www.youtube.com/watch?v=xTn7zdk3ykQ
