Upaniṣad: One of the Twenty-five Holy Methods of Perfect Penetration in Volume Five of the Śūraṅgama Sūtra

Original text:优波尼沙陀。即从座起。顶礼佛足。而白佛言。我亦观佛最初成道。观不净相。生大厌离。悟诸色性。以从不净。白骨微尘。归于虚空。空色二无。成无学道。如来印我。名尼沙陀。尘色既尽。妙色密圆。我从色相。得阿罗汉。佛问圆通。如我所证。色因为上。

Explanation: Upaniṣada immediately rose from his seat, and after bowing at the Buddha's feet, said to the Buddha: I also observed that after the Buddha first attained the Way, He taught the Dharma to the bhikṣus. I chose to cultivate the contemplation of the white skeleton, contemplating the impurity of the material body, and a strong sense of revulsion toward the material body arose in my mind. I awakened to the nature of all material forms: from impure white bones they turn into fine dust particles, gradually returning to empty space. I awakened to the fact that both emptiness and form are nonexistent, and attained the stage beyond training (aśaikṣa) of the fourth fruit. The Tathāgata confirmed me and named me Niṣada (subtle form). When the contemplative practice (vipaśyanā-caryā) reached its end and the forms of the six sense objects were exhausted within the mind, the wondrous forms contained profound and hidden secrets deep within them. I attained arhatship through the mark of form. The Buddha asked me about the dharma gate of perfect penetration; just as I myself realized it, contemplating the impurity of the material body is the most fundamental.

Upaniṣada cultivated the contemplation of the white skeleton, contemplating the impurity of the material body, visualizing the material body as white bones, then visualizing the white bones as subtle material sense-objects (rūpa-viṣaya), and finally the subtle material sense-objects vanished and became empty nothingness. All of this contemplative practice was carried out within profound meditative concentration (samādhi). The white bones manifested through this contemplative practice belong to the form born of meditative concentration (dhyāna-phala-rūpa), invisible to others; it can only be seen by oneself through the wisdom eye within meditative concentration. This seeing is not seeing with the physical eye, otherwise others could see it too. After he saw the white bones in meditation, he continued his contemplative practice, visualizing the white bones as the most subtle dust particles, close to the particles of empty space, and finally they transformed into nothingness; in his mind there was neither form nor emptiness—everything was emptied. These states all belong to the form born of meditative concentration; they are states of meditative absorption (samādhi), possessing both concentration and wisdom. Relying on this state of meditative absorption, one can attain liberation from the three realms.

If there is no meditative concentration, and one attempts to contemplate these dharmas, one can only imagine them with the mind consciousness, but one will never be able to visualize the white bones and the dust particles, let alone transform the dust particles into emptiness, and then empty even that emptiness. Therefore, the equal cultivation of Samādhi and Prajñā is called genuine practice, and only the result of genuine practice is called genuine realization. The cultivation and realization of all dharmas are like this; there is no other shortcut, and meditative concentration cannot be avoided.