Nadi-janeu नाडी-जनेऊ nāḍī-janeū

“sacred thread”

Nadi-janeu is handed over to a disciple during choti-dikshaJaneu is a black woolen thread woven using a special technology from 8 finest threads. The janeu thread is associated with nada (or Shabda-Brahman), with three main energy channels (ida, pingala, sushumna), with six chakras, as well as with the gunas and doshas of the body. By receiving it, the disciple significantly changes his psychophysical structure. On this thread hangs ring, crystal, rudraksha, coral, and whistle. Ring or "pavitra" symbolizes the sun – source of prana and all the elements, pavitra is connected with the element of the earth, crystal or "sphatik" is the element of water, rudraksha – the element of fire, coral is the element of air, and whistle is the element of akasha and sound (nāda). All of them together are symbols of the five elements.

The janeu thread and the whistle (nadi) are used to worship Guru, Deities, Samadhi, which takes only a few seconds, but the effect of such puja is the most powerful, and it extends throughout the day. The thread and whistle help to direct prana into sushumna, yogin learns to regulate his prana in the body and his consciousness. This helps to recognize the inner sound, "anahata-nada", and dive deeper into it dissolving the mind, that is called nadanusandhana

This diksha has many subtleties. There is a certain mantra for nadi-janeu, and it protects against an influence of lower astral forces: bhutas, pretas, etc.