Ascetic practices, concentration and bodily postures described in the Vedas may have been precursors to yoga. According to Geoffrey Samuel, "Our best evidence to date suggests that [yogic] practices developed in the same ascetic circles as the early sramana movements (Buddhists, Jainas and Ajivikas), probably in around the sixth and fifth centuries BCE."
^ The Pāli and Sanskrit word bhāvanā literally means "development" as in "mental development." For the association of this term with "meditation," see Epstein (1995), p. 105; and, Fischer-Schreiber et al. (1991), p. 20. As an example from a well-known discourse of the Pali Canon, in "The Greater Exhortation to Rahula" (Maha-Rahulovada Sutta, MN 62), Ven. Sariputta tells Ven. Rahula (in Pali, based on VRI, n.d.): ānāpānassatiṃ, rāhula, bhāvanaṃ bhāvehi. Thanissaro (2006) translates this as: "Rahula, develop the meditation [bhāvana] of mindfulness of in-&-out breathing." (Square-bracketed Pali word included based on Thanissaro, 2006, end note.)
Tantra is a range of esoteric traditions that began to arise in India no later than the 5th century CE.[note 17] George Samuel states, "Tantra" is a contested term, but may be considered as a school whose practices appeared in mostly complete form in Buddhist and Hindu texts by about 10th century CE. Tantric yoga developed complex visualizations which included meditation on the body as a microcosm of the cosmos. They included also the use of mantras, pranayama, and the manipulation of the subtle body, including its nadis and cakras. These teachings on cakras and Kundalini would become central to later forms of Indian Yoga.
The Yoga Yajnavalkya is a classical treatise on yoga attributed to the Vedic sage Yajnavalkya. It takes the form of a dialogue between Yajnavalkya and Gargi, a renowned philosopher. The text contains 12 chapters and its origin has been traced to the period between the second century BCE and fourth century CE. Many yoga texts like the Hatha Yoga Pradipika, the Yoga Kundalini and the Yoga Tattva Upanishads have borrowed verses from or make frequent references to the Yoga Yajnavalkya. The Yoga Yajnavalkya discusses eight yoga Asanas – Swastika, Gomukha, Padma, Vira, Simha, Bhadra, Mukta and Mayura, numerous breathing exercises for body cleansing, and meditation.
Ascetic practices (tapas), concentration and bodily postures used by Vedic priests to conduct yajna (sacrifice), might have been precursors to yoga.[note 9] Vratya, a group of ascetics mentioned in the Atharvaveda, emphasized on bodily postures which may have evolved into yogic asanas. Early Samhitas also contain references to other group ascetics such as munis, the keśin, and vratyas. Techniques for controlling breath and vital energies are mentioned in the Brahmanas (texts of the Vedic corpus, c. 1000–800 BCE) and the Atharvaveda. Nasadiya Sukta of the Rig Veda suggests the presence of an early contemplative tradition.[note 10]
The early Buddhist texts describe yogic and meditative practices, some of which the Buddha borrowed from the śramaṇa tradition. The Pali canon contains three passages in which the Buddha describes pressing the tongue against the palate for the purposes of controlling hunger or the mind, depending on the passage. However, there is no mention of the tongue being inserted into the nasopharynx as in true khecarī mudrā. The Buddha used a posture where pressure is put on the perineum with the heel, similar to even modern postures used to stimulate Kundalini. Some of the major suttas that discuss yogic practice include the Satipatthana sutta (Four foundations of mindfulness sutta) and the Anapanasati sutta (Mindfulness of breathing sutta).