The Esala Full Moon day has many significant events in the Buddhist calendar. One Esala Full Moon day Buddha preaced his First Sermon, the Dhammacakkappavattana Sutra, to the five ascetics. It took place at the ‘Deer Park', near Benares, thereby inaugurating his public ministry.
The other noteworthy events connected with this day include the conception of the Bodhisatta in the womb of Queen Maya, the performance of the Twin Miracle (yamaka-patihariya), and he preached the Abhidhamma for the first time in Tavatimsa heaven.
One Esala full moon day at the age of tenety nine, prince Siddhartha renounced the worldly life and left his family. On this day his wife prince Ysodara gave birth to his son Prince Rahula.
An additional factor that enhances the value of this full moon day in Sri Lanka is that following the introduction of Buddhism, the first local ordination of a Sri Lankan, Prince Arittha, the nephew of the king entered the Order at Anuradhapura, under Arahant Mahinda Thera. Owing to the combination of all these events the Sinhala Buddhists fittingly observe this day ceremonially by holding Esala festivals throughout the island, The annual Esala Perahera in Kandy, is the most colorful traditional procession in the country.