Mandukya Karika, verse 4.81

Sanskrit text, IAST transliteration and English translation

अजमनिद्रमस्वप्नं प्रभातं भवति स्वयम् ।
सकृद्विभातो ह्येवैष धर्म धातुस्वभावतः ॥ ८१ ॥

ajamanidramasvapnaṃ prabhātaṃ bhavati svayam |
sakṛdvibhāto hyevaiṣa dharma dhātusvabhāvataḥ || 81 ||

81. (Reality which is) free from birth, (which is) free from sleep and dream, reveals itself by itself For, this Dharma (i.e., Ātman) is from its very nature ever-luminous.

Shankara Bhashya (commentary)

The nature of that which is realisable by the wise is again described:—It (Ātman) reveals itself by itself. It does not depend for its revelation upon any external¹ light, such as the sun, etc. Self-luminosity² is its very nature. It is ever-luminous. This is the inherent characteristic of the Dharma, known as Ātman.

Anandagiri Tika (glossary)

¹ External, etc.—Ātman itself is the substratum of everything. Therefore it cannot be dependent upon anything else.

² Self-luminosity—Ātman is called self-luminous as, in the state of deep sleep, the real nature of Ātman is revealed though all external instruments such as the sense-organs, the mind, etc., then remain inactive.

The text characterises Ātman as free from dream and sleep. Dream indicates the wrong apprehension of truth while sleep stands for its non-apprehension. The waking state is omitted as because either it is included in the dream state or it stands for the state of knowledge.