Bhagwad Gita
Chapter 6, Verse 13
समं कायशिरोग्रीवं धारयन्नचलं स्थिरः।
संप्रेक्ष्य नासिकाग्रं स्वं दिशश्चानवलोकयन्।।6.13।।
Let him firmly hold his body, head, and neck erect and still, gazing at the tip of his nose without looking around.