But those who practise penance and faith in the forest, tranquil, wise, and living on alms, depart free from passion through the sun to where that immortal Person dwells whose nature is imperishable.

In plain words: But some people live simply in the forest with self-discipline and faith. They are calm and wise and live on what others give them. Free from desire, they pass through the sun to where the undying, eternal Being lives.