Devi Kamakshi resides in the form of the light that emanates from the lamp. This lamp is used in temples as the main source of fire for other smaller lamps lit during festivals or auspicious days like Tuesdays, Fridays, Sundays. The "Deepam" denotes knowledge, and eradicates the darkness or ignorance in us. The Goddess Kamakshi in the form of light illuminates the knowledge in us and drives out the ignorance. That is why we worship the Light in the form of Kamakshi. Thus the knowledge that we gain removes totally the ignorance just like the light removes darkness. While the deepam glows all the negative tendencies get burnt out just like the wick. Once the wick gets burnt out, all the negative tendencies will slowly get eliminated