Furthermore, by one (nāḍī), upward, udāna (leads): by merit, to the world of merit; by demerit, to the world of demerit; by both, to the human world.

This verse describes the function of udāna at the moment of death and its role in determining the destiny of the soul.

Athaikayā ūrdhvaḥ — furthermore, by one (nāḍī), upward. This special nāḍī is suṣumnā, the central channel that ascends from the base of the spine to the crown. While vyāna circulates horizontally through the 72,000 nāḍīs, udāna has an exclusively vertical movement.

Udānaḥ — the ascending prāṇa. Ud- means “upward”. Udāna is the force that elevates: it produces speech (raising air from the lungs), swallowing (raising food), and at the moment of death, it raises the soul out of the body.

Puṇyena puṇyaṃ lokam — by merit, to the world of merit. If the accumulated karma is predominantly positive (puṇya), udāna leads the jīva toward heavenly realms (svarga), states of subtle enjoyment.

Pāpena pāpam — by demerit, to the world of demerit. If negative karma (pāpa) predominates, the destiny is downward, toward realms of suffering.

Ubhābhyām eva manuṣyalokam — by both, to the human world. Human birth results from a mixture of merit and demerit. This is why human life contains joy and suffering: it is the fruit of mixed karma.

For the yogī, this teaching has practical implications: by purifying karma and consciously awakening udāna (through prāṇāyāma, meditation and virtuous living), one can direct one’s own final transition toward liberation (mokṣa), completely escaping the cycle of rebirth.