Story behind Karthigai
Once Brahma and Vishnu due to the ego started arguing with each other " who is the greatest". Both claimed to be the greatest, instead of doing their duty. At that time the God Shiva appeared in the form of fire and told them whoever finds the top or bottom of the fire is the greatest. Brahma took the form of Annam (a bird) and tried to find the top of the frle pillar. Vishnu took the form of Varaha( giant pig) and tried to see the bottom of the pillar. As the God has no limit in his size or power, both of them could not see either top or bottom of the fire. When their ego went down and they prayed the God, He appeared before them. The day in which the God appeared as a pillar of fire is Thirukarthigai/Karthigai Deepam.
This vradha indicates the non measurable infiniteness of the God and shows that the God is the light that will drive away our ignorance. Lamps are lit in the houses to pray His "Jyothi Swarupam".
First day of this festival is called as "Appakarthigai" and the second day is called as "vadai karthigai". All devotees will offer pori,adhirasam,vella Seedai, vetrilai pakku,fruits as neivedhyam for God Shiva.
In down South of Tamilnadu and in Kerala, Hindus will pray god for goodness of their brothers and they will light a elephant lamp(Gajalakshmi Vilaku) which marks as a sign of prosperity and wealth. The story behind lighting elephant lamp(Gajalakshmi Vilaku) is given below.
So we on this auspicious occassion all devotees should chant the following lines