Why is Chhath offered to the setting Sun first?
छठ में पहले डूबते सूरज को अर्घ्य क्यों दिया जाता है?
The short answer
No text we could confirm gives a single reason. The structure of the vow gives you part of the answer: Chhath belongs to Shashthi, the sixth lunar day, whose evening is the first offering, and the fast closes at the following sunrise. People have added their own meanings to that order, and the most common is that a person who honours the setting Sun doesn't only honour what's on the rise.
How the days fall
The festival runs over about four days in the bright fortnight of Kartika. The first day is Nahay Khay, a bath and a simple meal. The second is Kharna, an evening meal of rice and jaggery kheer, after which a dry fast begins for many who keep the vow. The third day is Shashthi, when you stand in water at sunset and make the Sandhya Arghya. The fourth is Saptami, when you return before dawn for the Usha Arghya, and only then does the fast end.
So sunset comes first because the festival is anchored to the evening of Shashthi, and the morning that follows is what closes it. That describes the order, but of course it doesn't explain why the vow was built this way.
Who is the “Chhathi Maiya”?
The name Chhath comes from the Sanskrit ṣaṣṭhī, “sixth”, and the festival joins the Sun with a goddess. Chhathi Maiya is often linked with Shashthi Devi, a protector of children in the Brahma Vaivarta Purana, who is identified as a part of Prakriti. Writers at Sahapedia also connect her with Devasena, wife of Kartikeya. That helps explain the tithi and the prayers for children. It does not explain the sunset order, and we couldn't find a named text that does.
What people say the setting Sun means
You'll hear that the Sun has two consorts, Usha, dawn's first ray, and Pratyusha, its last, and that the evening offering is for one and the morning for the other. You'll also hear that Sita kept this fast on returning to Ayodhya, that Draupadi kept it too, and that Karna began it by standing in water to worship the Sun. The Mahabharata does show Karna worshipping the Sun, but we haven't found the epics naming Chhath, so these links are best taken as oral tradition.
The saying that moves people most is simple: everyone bows to the rising Sun, and here you bow to the setting one too. As far as we can tell it's a living folk reading, not a scriptural statement, and it's a good one.
One reading: an all-night arc
Put together, the two offerings bracket a long night of waiting. You offer to the Sun as it leaves, sit up with your family and with the songs of the season, and meet it again as it comes back. Whatever its origin, that shape gives the festival much of its emotional force. This is our reading of it, not a documented intention.
“Chhath is solar science: the Sun's rays at sunrise and sunset are free of harmful UV, and the ritual detoxifies your body and builds energy.”
- What's true
- Sunlight near the horizon passes through more atmosphere, so UV is much lower then.
- Detoxification
- We found no study showing that this ritual removes toxins. The word is doing no measurable work here.
- Vitamin D
- Skin makes vitamin D using UVB, so a low Sun, if anything, gives you less of it.
- Origin
- We found no early text stating this as the reason for the timing.
A correct fact about low sunlight has been turned into a health claim that nobody has shown. The fast itself is demanding, and those who keep it know that. The festival's meaning comes from devotion, not from these claims.
Ask your elders
“If your family keeps Chhath, ask who keeps the fast now and who kept it before. Which song still makes them cry at the ghat? Ask what they were told as children about why they went to the river in the evening first.”
Sources
- Shruti Chakraborty, “Chhath Puja: Origin of the Festival, and the Story of Devasena”, Sahapedia
- K. S. Singh, “Solar Traditions in Tribal and Folk Cultures of India”, as cited by Sahapedia
- Brahma Vaivarta Purana (Shashthi Devi, work-level)
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