"To write the fu: Click the teeth thrice. Fill the mouth with clear water, and spray it towards the east...."
" The spell: Brightly, brightly, Yin & Yang, / the Sun comes out from the east/ I respectfully 敕 write this talisman/ to completely sweep away all that is inauspicious/ the mouth spews the 3 Kinds of fire[1] ...
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(3) Sha is the term used to refer to an evil force in general.