Mandukya Karika, verse 1.25

Text

युञ्जीत प्रणवे चेतः प्रणवो ब्रह्म निर्भयम् ।
प्रणवे नित्ययुक्तस्य न भयं विद्यते क्वचित् ॥ २५ ॥

yuñjīta praṇave cetaḥ praṇavo brahma nirbhayam |
praṇave nityayuktasya na bhayaṃ vidyate kvacit || 25 ||

25. The mind should be unified with (the sacred syllable) Aum. (For) Aum is Brahman, the ever-fearless. He who is always unified with Aum knows no fear whatever.

Shankara Bhashya (commentary)

The word Yuñjīta means to unify, i.e., to absorb. The mind should be absorbed in Aum, which is of the nature of the Supreme Reality, as explained before. The Aum is Brahman, the ever-fearless. He who is always unified with Aum knows no fear whatever; for the Śruti says, “The knower of Brahman is not afraid of anything”.