When the breath is unstable, the mind is unstable. When the breath is stable, the mind stabilizes, and the yogī attains immobility. Therefore, he should control the breath.

This verse establishes the fundamental principle of prāṇāyāma: the direct connection between breath (vāyu/vāta) and mind (citta).

Cale-cala and niścale-niścala form a perfect parallelism: agitated breath = agitated mind; still breath = still mind. The relationship is bidirectional, but Haṭha Yoga emphasizes working from the breath because it is more accessible to voluntary control.

Sthāṇutva (immobility, pillar-like firmness) describes the state of the established yogī. It is not dead rigidity but living stability — like a rooted tree that can bend without breaking.

Tato vāyuṃ nirodhayet (therefore, he should control the breath) derives practice from principle. The logic is irrefutable: if you want a stable mind and breathing determines it, work with the breath.

This understanding revolutionizes practice: instead of fighting directly with thoughts, you regulate the breath and the mind quiets as a side effect.