摩訶止觀 8.188

8.188

治時媚鬼者：須善識十二時、三十六時獸，知時唱名，媚即去也。隱士頭陀人多畜方鏡，挂之座後，媚不能變鏡中色像，覽鏡識之，可以自遣。此則內外兩治也。

Remedying seasonal enchanting spirits: one must clearly recognize the twelve double-hours and the thirty-six seasonal beasts; knowing the time, chant its name, and the spirit will depart. Hermits and dhūta practitioners often keep a square mirror hanging behind their seat; the spirit cannot transform its form and appearance within the mirror; seeing it in the mirror and recognizing it, one can banish it oneself. This is both internal and external remedy.