The Śūraṅgama Sūtra, Volume Five: Aniruddha among the Twenty-five Sages' Methods of Perfect Penetration

Original text:阿那律陀。即从座起。顶礼佛足。而白佛言。我初出家。常乐睡眠。如来诃我为畜生类。我闻佛诃。啼泣自责。七日不眠。失其双目。世尊示我乐见照明。金刚三昧。我不因眼。观见十方。精真洞然。如观掌果。如来印我。成阿罗汉。佛问圆通。如我所证。旋见循元。斯为第一。

Explanation: Aniruddha rose from his seat, paid homage at the Buddha's feet, and said to the Buddha: When I first left home, I always loved to sleep, and the Tathāgata rebuked me, saying I slept greedily like an animal. Hearing the Buddha's rebuke, I repented and blamed myself, going seven days without sleep, and ruined both my eyes. World-Honored One, you then taught me to cultivate the Vajra Samādhi of Delightful Seeing and Illumination.

After this Vajra Samādhi was cultivated, I could see the scenes of the worlds in the ten directions without relying on my physical eyes—everything exceedingly fine and real, penetratingly clear and unobstructed, just like observing an āmalaka fruit in my own palm. The Tathāgata then certified me as having become an arhat. When the Buddha asked about the method of perfect penetration, it was just as I had realized: turning the seeing back around to trace its source—whereas the eyes had formerly looked outward at objects, I instead looked inward, contemplating the source of the ability to see form, and realized that form is empty and that self is empty, becoming an arhat beyond training (the fourth fruit). This is the foremost dharma gate that I cultivated and realized.

Aniruddha cultivated this Vajra Samādhi of Delightful Seeing and Illumination, every day using his mind-eye to introspect on what exactly the ability to see form is, and how form is seen. His meditative concentration grew ever deeper, and the wisdom of his contemplative practice (vipaśyanā-caryā) grew ever deeper as well. Finally he found the source, the samādhi appeared, and the divine eye immediately manifested, whereupon he attained the fourth fruit.

When cultivating the path, if precepts, meditation, and wisdom are all completely fulfilled and one is extremely diligent, the Vajra Samādhi will inevitably manifest. This is a model of genuine practice. It is not like some people who are content with diligently learning a bit of knowledge and think they have arrived, their arrogance blazing while they amount to nothing. Knowledge accumulated by the mind consciousness is like a castle in the air—after death nothing remains, and the manas goes destitute to future lives together with the tathāgatagarbha. What could it possibly have?