The Rishi says, those who seek the true self, through austerity, chastity, faith and knowledge, they, by the Northern route–a journey that is upwards–gain the domain of the Sun. The Sun who shines in the uppermost reaches, and is the support of all life breaths. Mukya Prana, the Supreme Prana supports all other Pranas or movement of breath in the body.
When one has reached the end of the Northern path, the Sun, eternal and fearless–one does not have to come back into this world of sorrow. This is the final goal.
Etat parayanam etasman na punar avartanyte
Such people are not reborn. That is the final goal, parayanam. Na punaravartanyte–from that they do not return. This verse is about the cessation of conditioning. It is about those who have reached the Supreme abode, the Supreme Being–the true Self that frees one from being re-born again. Having reached the true Self, one remains eternally free and unconditioned.
About the Supreme Being, it is said they speak of him as the Father. The Father is the creator of all. The Being that has five feet and twelve forms, seated in the higher half of the heavens, full of water. And then again, others speak of him as the omniscient sitting on a chariot of seven wheels and six spokes. Now, this needs quite a bit of explanation.