In this Upanishad, students of Sage Pippalada ask him questions about Brahman.
Sage Pippalada explains that those who observe austerity and chastity and in whom truth is firmly established alone can attain Brahmaloka (World of Brahma). The stainless World of Brahma belongs to those in whom there is no crookedness, no falsehood, no deception. By meditating on the syllable AUM, the seeker becomes one with the Purusha or the Supreme Brahman and there by becomes all knowing. Finally the Sage concludes by saying that he knows the Supreme Brahman and that there is nothing higher than this.
Prana or the life-energy is explained in this Upanishad. Prana is not material, it is not physical, but it is something that maintains and sustains the body. The source of the Prana is the Supreme God. Prana is divided into five parts: prana, apana, samana, vyana and udana. The life-energy that is inside the physical eyes, nose and ears, is called prana. The life-energy in our organs of excretion and generation is apana. Samana is the life-energy that governs our digestion and assimilation. In the lotus of the heart, where the Self is located, there are one hundred and one subtle spiritual nerves, and in each nerve one hundred nerve branches, and from each nerve branch seventy-two thousand nerve branches. There the prana that moves is called vyana. Through the center of the spine, life-energy flows. When it goes upward it reaches the Highest, and when it goes downward it reaches the lowest. When a seeker of the infinite Truth leaves the body, this prana rises towards the Highest, and when a sinful person leaves the body, this prana goes downward. This prana, which flows through the center of the spine, is called udana.