Diwali in Jainism is mainly the day Mahavira attained nirvana (moksha). Here is the simple meaning and practice:

• Why celebrated: It marks the nirvana (liberation) of Lord Mahavira, the 24th Tirthankar, in Pawapuri in 527 BCE. It is a reminder to follow ahimsa (non-violence), truth, and self-discipline. Some traditions also note that Gautama Swami, Mahavira’s chief disciple, attained omniscience the next day.
• How it is observed: Jains light lamps to symbolize the removal of spiritual darkness and ignorance, gather for prayers, recite important verses, and often fast or practice restraint during the festival. In many communities, Diwali also signals the end of the rainy-season retreat and the new Jain year begins soon after.
• Differences between Digambar and Shwetambar: Both honor Mahavira’s nirvana, but exact customs (such as fasting duration, specific recitations, and calendar details) can vary between Digambar and Shwetambar Jains. The essential spirit remains: remembrance of Mahavira’s renunciation and guidance toward a more disciplined, non-violent life.

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