The Prashna Upanishad belongs to the Atharvaveda and is named for the six questions, prashnas, that six seekers of Brahman bring to Rishi Pippalada. They come to him with fuel in their hands, as students come to a teacher, and he asks them to live with him for a year in austerity, self-restraint and faith before they ask.
Kabandhi Katyayana asks where living beings come from, and hears of Prajapati bringing forth matter and life as a pair, and of the two paths after death — the southern path of the moon, which leads back, and the northern path of the sun, which does not. Bhargava Vaidarbhi asks which powers uphold the body; each claims the honour until breath rises as if to leave, and all must rise with it, as bees rise with the king of their hive. Kausalya Ashvalayana asks how breath is born and divides itself within the body, Sauryayani Gargya asks what sleeps in a person and what stays awake, and Shaibya Satyakama asks what one wins by meditating on Om. Sukesha Bharadvaja asks last about the person of sixteen parts, who is found within the body and into whom the parts return, as rivers lose their names in the sea.
The Prashna and the Mundaka belong together: both are of the Atharvaveda, both open with the peace chant bhadram karnebhih — may we hear with our ears what is auspicious — which also frames the Ganapati Atharvashirsha, and the commentary that tradition attributes to Adi Shankaracharya reads their teachings together. It comes fourth in the Muktika Upanishad's list of the ten principal Upanishads.