Light, symbolically speaking, has a lot of religious significance..The Holy Bible starts thus:
First God made heaven & earth. The earth was without form and void, and darkness was upon the face of the deep; and the Spirit of God was moving over the face of the waters. And God said, "Let there be light"; and there was light. And God saw that the light was good; and God separated the light from the darkness. God called the light Day, and the darkness he called Night.
This clearly illustrates (pun unintended) the concept of duality and the multiple references to light..
In Zoroastrianism, light is the great symbol of God and Goodness, whether in the light of the sun or in the sacred fire. The Spring Equinox and the lengthening of the days is thus a symbol of the victory of Light over the cold and darkness of winter. Zoroastrian rituals are conducted before a sacred fire. Some outsiders believe that they actually worship fire. This is not true. They regard fire as a symbol of their God, and they cherish the light that it produces. Light is seen as energy, a natural force that is powerful and necessary for survival.
A quote from the Holy Quran : God is the Guardian and Protector of those who believe; He brings them forth from darkness into light.
The Bhagavad Gita: The Light of Lights He is, in the heart of the Dark Shining eternally. Wisdom He is And Wisdom's way, and Guide of all the wise, Planted in every heart.
Given all this, the big irony is that we, the followers of these very religions, prefer to stay cubbyholed in the darkness of our ignorances and prefer not to see such obvious links amongst the faiths we follow...This Diwali let's light up these dark corners and resolve not to give into 'blind' faith...As quoted earlier in this post, Let there be light!! Outside as well as inside us..And what better day to start working on this than Diwali :) Happy Diwali Guys!