The works of Ādi Śaṅkarācārya

Bṛhadāraṇyakopaniṣadbhāṣyam

Verse 257

स वा एष महानज आत्माजरोऽमरो- ऽमृतोऽभयो ब्रह्माभयं वै ब्रह्माभयँ हि वै ब्रह्म भवति य एवं वेद ॥ २५ ॥

In plain words

This vast, unborn Self is who you are — untouched by age, unable to die, deathless by nature, without fear. This is Brahman. Brahman is fearlessness itself. And whoever knows this becomes, in truth, that very fearlessness.

Close to the Sanskrit

He, verily, is this great, unborn Self, undecaying, undying, immortal, fearless — Brahman. Brahman is fearless indeed. Truly, he who knows this thus becomes the fearless Brahman itself.