It is a four-day festival usually celebrated four days after Diwali.
The ritual of Chhath Puja includes taking the holy bath, fasting, standing and worshipping the sun for a long time and offering Prasad and Arghya to ‘Rising and setting Lord Surya”. Some worshipers observe fasting even without water for 36 hours continuously.
Devotees during this period observe purity and live frugally. They sleep on the floor on a single blanket.
* Nahay Khay – First DayNahay Khay means bath and eat.
On the first day of Chhath Puja, devotees take a dip in the river Kosi, Karnali or Ganga whichever is near to their residence and bring home the holy water from these rivers to prepare the offerings.The house and surroundings are fully cleaned. The devotees observing fast (Vrata) are called Vratin or Parvaitin only takes one meal on this day. This meal is called as kaddu-bhat cooked only by using the bronze or soil utensils and mango woods over the soil stove.
* Lohanda and Kharna (Argasan) – Second DayOn the second day of Chhath Puja, the devotees keep fast for the whole day and break their fast in the evening after sunset after the worship of Sun. After taking the meal in the evening, they go on a fast without water for the next 36 hours.
* Sandhya Arghya (evening offerings) – Third DayOn this day devotees prepare prasad (offerings) at home. After preparing the prasad, on the eve of this day, the Vratins make the offerings to the just setting sun at the riverbank, pond or a common large water body.
They are accompanied by their friends and family and numerous other participants and onlookers, all willing to help and receive the blessings of the worshipper.
At the night of Chhath, a vibrant event of Kosi is celebrated by lighting the lamps of clay diyas under the covering of five sugarcane sticks.
The five sugarcane sticks indicate the Panchatattva (earth, water, fire, air, and space) that the human body made of Panchatattva.
* Usha Arghya (morning offerings) – Fourth DayOn the fourth and final day, the devotees along with family and friends, go to the riverbank before sunrise, in order to make the offerings (Arghya) to the rising sun.
The festival ends with breaking of the fast by the Vratins by having Chhath prasad.