Like the Katha Upanishad, the Mundaka Upanishad is a short, clear presentation of some the central ideas of the Upanishads. It contains some of the most beautiful poetry of the Upanishads.
The first section describes the ritual preparations for understanding Brahma and the effects of ceremonial observances. The second section appears to owe much to the earliest Upanishads, metaphorically describing Brahma as the body of the universe. Many of its passages suggest a pantheistic understanding of the world; however, it also beautifully describes the origin of particulars:
As, from a well-blazing fire, sparks
By the thousand issue forth of like form,
So from the Imperishable, my friend, beings manifold
Are produced, and thither also go.
The final section describes the method by which salvation is achieved, expressing views and practices that are consonant with Buddhism. There is a recognition that desire is the cause of rebirth and that this can be avoided through practicing austerity. Certainly there is an element of self-denial, sacrifice and asceticism here; however, this should not be over emphasized. More certainly exercising discipline is more to the point, such that one does not become distracted and so lost in the pursuit of the ephemeral events and pleasures of the illusory world.