攝大毘盧遮那成佛神變加持經入蓮華胎藏海會悲生曼荼攞廣大念誦儀軌供養方便會 2.22

2.22

Bend the prajñā hand into a fist; place the wind joint between the eyebrows.
This is called the Ūrṇā-Treasury; the Buddha constantly fulfills their vows.
By merely forming this, one is instantly identical to the Supreme Among Men.