Lakshmi Puja on Diwali:
There are two legends that associate the worship of Lakshmi on this day. According to the first legend, on this day, Lakshmi emerged from Kshira Sagar, the Ocean of Milk, during the great churning of the oceans, Samudra Manthan.
The second legend (more popular in western India) relates to the Vamana avatar of the big three Vishnu, the incarnation he assumed to kill the demon king Bali. On this day, Vishnu came back to his abode the Vaikuntha; so those who worship Lakshmi receive the benefit of her benevolent mood, and are blessed with mental, physical and material well-being.
May Goddess Lakshmi shower you with abundant happiness on this auspicious festival of Diwali!