B.G 6.13 and 14

समं कायशिरोग्रीवं धारयन्नचलं स्थिरः। सम्प्रेक्ष्य नासिकाग्रं स्वं दिशश्चानवलोकयन् ॥१३॥

प्रशान्तात्मा विगतभीर्ब्रह्मचारिव्रते स्थितः। मनः संयम्य मच्चित्तो युक्त आसीत मत्परः ॥१४॥

Keeping evenly the body, the head, and the neck; wearing the object of meditation in the mind; keeping the mind steady and not wandering; having fixed the gaze at the tip of the nose and not looking in other directions; having a tranquil self that is free from fear; controlling the mind and having established in the vow of celibacy; must unite his consciousness in Me and be situated in Me as the supreme goal.