This is a small work counted among the minor Upaniṣads and is said to belong to the Śukla Yajurveda. It is devoted to a description of the bhikṣus or mendicants or saṁnyāsins.
The bhikṣus desiring for mokṣa or liberation are of four types: the kuṭīcakas, the bahūdakas, the haṁsas and the paramahaṁsas.
The kuṭīcakas take eight grāsas or mouthfuls of food daily and strive for mokṣa through the path of yoga. Gautama, Bharadvāja, Yājñavalkya, Vasiṣṭha and others belong to this group.
The bahūdakas wear the insignia of a monk like red-robes, three bamboo staves tied together, a water-pot and so on. They too live upon eight mouthfuls of food got by begging. They avoid honey and flesh even though offered by the host.
The haṁsas are itinerant monks who do not stay in a place for more than a day if it is a village or five days if it is a city or seven days if it is a place of pilgrimage. They observe the Cāndrāyaṇa rite and practise yoga to obtain mokṣa.
The paramahaṁsas like Saṁvartaka, Āruṇi, Śvetaketu, Jaḍabharata, Śuka and others sustain themselves on eight mouthfuls of food, practise yoga and pray for attaining mokṣa.
The Upaniṣad gives a long description of their way of life. They live in secluded places like abandoned houses, burial grounds, temples or under trees or on the banks of rivers. They are unconcerned about their dress and may even move about naked. They accept alms from all, irrespective of their caste. They have transcended all dualities like good and bad and ever contemplate on the Ātman. Living thus they give up the body when the time comes to depart.