The full moon day in Kartik, the first month of the Indian calendar brings in the festival of Dev Diwali. For the Jains, it is the day of 'Nirvana' of Lord Mahavira, the twenty-fourth Tirthankara. To them it is the Deva Diwali when Lord Mahavira is worshiped, Agams (Jain holy books) are read and homes and temples are illuminated. Lamps are lit under the moonlight sky and a family feast celebrates this day.
Thousands of Jain pilgrims from all over India flock to the sacred Mount Girnar in Gujarat where special celebrations are held on this day. It is said that the first scriptural reference to Diwali is found in the Jain scripture Harivamsha Purana, by Acharya Jinasena. None of the principal Hindu scriptures mention the festival in particular. This has made some believe that , Diwali was originally a Jain festival and later adopted by Hindus as a festival of their own.
Lord Mahavira, the last of the Jain Thirthankaras, said to have attained Nirvana on this day at Pavapuri. Accoriding Jain legends the first disciple of Mahavira, Ganadhar Gautam Swami also attained complete knowledge on this very day, thus making Diwali a really special occasion for the Jains to celebrate.
The way Jains celebrate Diwali is different in many respect. There is a note of asceticism in what ever the Jains do and the celebration of Diwali is not an exception. The Jains celebrate Diwali during the month of Kartik for three days. During this period, devoted Jains observe fasting and chant the Uttaradhyayan Sutra which contain the final pravachans of Lord Mahavira and meditate upon him.