Bhagavad Gita, Chapter 11, Verse 24

On seeing You touching the sky, shining in many a colour, with mouths wide open, with large fiery eyes, I am terrified at heart, and find no courage nor peace, O Vishnu.

Even real courage, the kind Arjun is known for, is described as failing him completely in this moment.

This isn't a small tremor of nerves, Arjun names losing both his composure and his peace of mind outright. Real vulnerability is spoken here without any attempt to appear unshaken.