Korean monastics practice intensive meditation twice a year for three months.
Those meditation retreats called angeo in Korean usually begin on the fifteenth
day of the fourth lunar month in summer and on the fifteenth day of the tenth
lunar month in winter.
Also, Buddhist monks would be staying indoors rather than
getting wet and stepping on worms on the ground during rainy season. In addition,
during the rainy season, there are many worms on the ground during rainy season. In addition,
intent on not stepping on them, considering it better to stay indoor.
On the final day of a retreat monastics
perform a ceremony of repentance,
which is an opportunity to review their meditation experiences and
repent of their own wrongdoing.
On the final day of the summer retreat monastics offer a special festival to feed hungry ghosts,
and this festival is called Ullambana
(Uranbunjeol or beakjung in korean)