Kartika Purnima

Kartika Purnima

October-November; full moon day of Hindu month of Kartika
Hindus celebrate Kartika Purnima in honor of the day when God incarnated himself as the Matsya Avatar in fish form. According to Hindu mythology, the purpose of this incarnation was to save Vavaswata, the seventh Manu and progenitor of the human race, from destruction by a deluge. Good deeds done on this day are believed to earn high religious merit. Bathing in the Ganges or in other holy water is considered to be of special religious significance. Hindus spend the day fasting, meditating, and performing charitable acts.
It is also believed the Shankara killed the demon Tripurasura on this day, for which he is also called the Tripurari. Shiva is worshipped on this occasion, and giving a bull (Shiva's mount) as a gift to a Brahman is considered to be an appropriate and significant act. For this reason, it is common to hold cattle fairs on this day.
SOURCES:
RelHolCal-2004, p. 178