The importance of lighting a diya during worship can be traced back to Vedas. Light symbolizes knowledge and darkness, ignorance. The Lord is the Knowledge Principle (chaitanya) who is the source, the enlivener and the illuminator of all knowledge. Hence light is worshipped as the Lord Himself. Knowledge removes ignorance just as light removes darkness. Also knowledge is a lasting inner wealth by which all outer achievements can be accomplished. Hence we light the lamp to bow down to knowledge as the greatest of all forms of wealth. We therefore keep a lamp lit during all auspicious occasions as a witness to our thoughts and actions.
