Here is your paragraph on Sravana Purnima:
Sravana Purnima is a very significant ceremonial event in the life of most Hindus. This is a special festivity associated with the annual renewal of the sacred thread.
This falls on the full moon day of the month of Shravana (July-August).
This festival is not consecrated to any specific deity but there is a legend that this is one of the four major festivals initiated by Vishnu for the four principal castes
Sravana Purnima for the Brahmins
Dasara for the Kshatriyas
Diwali for the Vaisyas
Holi for the Sudras.
The purpose of the renewal of sacred thread is to dedicate oneself again to the performance of one’s ritual commitments, and to recognize the importance and holiness of the sacred thread worn by Brahmins.
The exchange of the old thread for the new is generally done ritualistically on a collective basis. Throngs of men, clad in clean white after an early bath, gather at some public place such as the precinct of a temple, a school hall or whatever. Under the direction of several gurus they repeat the necessary mantras in front of little altars where burning twigs keep alive the sacrificial symbol.
They pay their homage to Ganesa, the Sapta Rishi and Arundhati, who are among those whose names are invoked during the diurnal spiritual exercises associated with the sacred thread. Then, after the new thread is carefully put on, the old one is removed and cast away in the fire. Normally one repeats the Gayatri mantra 108 times at every sitting, but this day calls for 1008 repetitions.
There is a happy atmosphere throughout the ceremonies. The clang of the little brass cups with holy water and mini-spoons and the audible chanting of the mantras by many groups, often out of phase, produce a peculiar musical effect that has its strange and elevating ring. Then there is the aroma of burning twigs and the scattering of the darbha grass. The arrangement of betel nuts on a tray is part of the required ritual for monetarily recognizing the guru’s services, a custom that is associated with practically every Hindu religious occasion.
When the men return home, the women-folk receive them ceremoniously, and serve them a specially prepared feast. See also (‘Narali Purnima’, ‘Rakhi Purnima’ Upakarma and Gayatrijapam)