The Poson Full Moon day is the second most important day for Sri Lankan Buddhists. It was on this day in the year 247 BC that Theras Itthiya, Utthiya, Sambala, Bhaddasala and Sumana Samaneras headed by Arahat Mahinda met the King Devanampiyatissa at Missaka Pabbata, while the King was hunting deer.

Suddenly the King heard someone calling him by his name “Tissa,Tissa” The King was taken by surprise as nobody would dare call him by his name. The King Looked up and saw a person dressed in saffron robes. He inquired as to who they were? Arahat Mahinda replied,

“Samanamayam maharaja - dhamma rajassa sravaka
Thameva anukampaya - Jambudeepa idagatha”

Arahat Mahinda explained that they were disciples of the Buddha who had come from Jambudeepa. Devanampiya Tissa then realized that his friend had sent them. He put down his weapons and approached the Arahat. He greeted him and both sat comfortably with their respective followers.

Arahat Mahinda realized that the King was a very intelligent person. The wise Thero preached Culahatthipadopama Sutra. At the end of this discourse the King and his retinue embraced the new faith. King Devanam Piya Tissa put down his bow and Arrows, never to pick up again. In Sri Lanka Arahant Mahinda Thera is reverently called Anubudu.