Lighting a deepam(oil lamp) in a house is considered auspicious. A lamp is lit every day by a member of the household in the morning and worshipped as an image of the Almighty himself. In some houses a lamp is left to burn at all time of the day. Only oil or ghee is used to feed the flame which is left burning symbolising the good fortune of the household.
Suklambharadharam vishnum Sasivarnam chaturbhujam
prasanna vadhanam dhyaayaeth sarvavignoapaSaamtayae
We light lamp chanting the above mantram and the oil lamp is decorated with Kumkuma(vermilion) and Akshimtalu(turmeric colored rice.)
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