
Chhat Puja is celebrated twice a year: once in the
summers (May-July), called the Chaiti Chhath, and once in the winters
(September-November) around a week after Deepawali (Diwali), called the Kartik
Chhath. The latter is more popular because winters are the usual festive
season in North India, and Chhath being an arduous observance, requiring the
worshippers to fast without water for more than 24 hours, is easier to undertake
in the Indian winters.
Because Chhath is mainly a Bihari festival,
wherever people from Bihar have migrated, they have taken with them the tradition
of Chhath. This is a ritual bathing festival that follows a period of abstinence
and ritual segregation of the worshiper from the main household for four days.
During this period, the worshiper observes ritual purity, and sleeps on the
floor on a single blanket. The main worshipers, called Parvaitin (from Sanskrit
parv, meaning 'occasion' or 'festival'), are usually women.

However, a large number of men also are
the main worshiper. The parvaitin pray for the well-being of their family, for
prosperity and offspring. They usually can perform Chhath only if it is passed
on to them from their older generation. However, once they decide to do it,
it becomes their duty to perform it every year, the festival being skipped only
if there happens to be a death in the family that year.
Houses are scrupulously cleaned on the
eve of Chhath and so are the surroundings. One the first day of the festival,
the worshiper cooks a traditional vegetarian meal and offers it to the Sun God.
This day is called Naha-Kha (literally, 'Bathe and eat'!). The worshiper allows
herself/himself only one meal on this day from the preparation.

On the second day, a special ritual,
called Kharna, is performed in the evening after Sun down. On this day also,
the worshiper eats his/her only meal from the offerings (Prashad) made to the
Sun God in this ritual. Friends and family are invited to the household on this
day to share the prashad of the ritual. From this day onwards, for the next
36 hours, the worshiper goes on a fast without water. The evening of the next
day, the entire household accompanies the worshiper to a ritual bathing and
worship of the Sun God, usually on the bank of a river or a common large water
body.
The occasion is almost a carnival. Besides
the main worshiper, there are friends and family, and numerous participants
and onlookers, all willing to help and receive the blessings of the worshipper.
Ritual rendition of regional folk songs, carried on through oral transmission
from mothers and mothers-in-law to daughters and daughters-in-law, are sung
on this occasion. The same bathing ritual is repeated on the following day at
the crack of dawn. This is when the worshipper breaks his/her fast and finishes
the ritual.Chhath being celebrated at the crack of the dawn on a river bank
is a beautiful, elating spiritual experience connecting the modern Indian to
his ancient cultural roots.

The folk songs sung on the eve of Chhath
mirror the culture, social structure, mythology and history of Bihar and Uttar
Pradesh. Nowadays, modern Chhath songs, largely Bollywood filmy remixes have
caught on, but the old tradition still goes strong with a great degree of sanctity.
The three main linguistic regions of Bihar: the Maithili, the Magadhi, and the
Bhojpuri, and all the various dialects associated with these, have different
folk songs; but all dedicated to Chhath, they have an underlying unity. The
minor nuances of the Chhath rituals, such as in the Kharna ritual, vary from
region to region, and also across families, but still there is a fundamental
similarity.