Bhagavad Gita Chapter 4, Verse 29

अपाने जुह्वति प्राणं प्राणेऽपानं तथापरे | प्राणापानगती रुद्ध्वा प्राणायामपरायणाः ||

apāne juhvati prāṇaṁ prāṇe 'pānaṁ tathāpare prāṇāpānagatī ruddhvā prāṇāyāmaparāyaṇāḥ

Some offer the in-breath into the out-breath. Others offer the out-breath into the in-breath. Others, restraining the flow of in-breath and out-breath, are devoted to the practice of breath control.

Krishna describes breath control (pranayama) as a form of sacrifice. 'Apāne juhvati prāṇaṁ' (offering in-breath into out-breath) means some practitioners focus on exhalation. 'Prāṇe 'pānaṁ' (offering out-breath into in-breath) means others focus on inhalation. 'Prāṇāpānagatī ruddhvā' (restraining the flow) means controlling both breaths, holding, suspending. This verse shows that pranayama (breath control) is a form of yajna—when you control breath consciously, it becomes offering rather than automatic function. Breath control isn't just physical exercise—it's a form of sacrifice that transforms the relationship with the body and mind. This verse continues the theme that different practices can be forms of sacrifice when done with the right attitude.