Abhidhamma Day.

Why do we celebrate Abhidhamma day?
In the Theravada tradition, The Full Moon Day of Thadingyut (full moon of october) is the Lighting Festival of buddhist specially the burmese.The celebration of this festival is to illuminate the anniversary of Buddha's return from heaven (Savatimsa) where He had spent three months. Queen Mayadevi died after giving birth to Buddha. She was reborn in heaven. Seven years later, the Buddha went to heaven in order to express gratitude to His mother. He preach the Abhidhamma (the supreme teaching of Buddha) to His mother goddess and the other gods. The Buddha returned from heaven to the human world, people from all over the country lit candles to welcome Him back. He descended on a stare made by the King of Devas. Humans, devas and the beings in hells can look each other for this miracle.