大毘盧遮那成佛經疏 13.202

13.202

次佛眼印。作三補吒，雙屈地水入掌，竪二火令如針，二風指轉捻二火指第三節上，由如眼形。二空指並竪稍屈，令當二中指下，使指頭如竪眼之形。即是三昧也。其地水指如向內合掌之法，如前名為佛母印。此中名佛頂印，亦名佛菩薩母印也。

Next is the Buddhalocanā mudrā. Form a saṃpuṭa, bend both earth and water fingers into the palms, erect the two fire fingers like a needle, and twist the two wind fingers to press upon the third joints of the two fire fingers, forming the shape of eyes. Erect the two space fingers together, bending them slightly, placing them below the two middle fingers so that the fingertips form the shape of a vertical eye. This is the samādhi. The earth and water fingers follow the method of the inward añjali; as before, it is called the Buddha Mother mudrā. Here it is called the Uṣṇīṣa mudrā, and also called the Mother of Buddhas and Bodhisattvas mudrā.