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 2.43

2.43

Join samādhi and prajñā into a fist, and bend the prajñā-wind like a hook;
this is indeed called the Hook mudrā. The Buddhas, the Saviors of the World,
summon all those abiding in the stages of the ten bhūmis,
those with the great mind of bodhi, as well as sentient beings of evil intentions;
upon being summoned, all assemble.