Parents and elders also receive obeisance from younger members of the family at the beginning as well as the end of lent, after the tradition established by the Buddha himself. It was during Vassa that he ascended to the Tāvatiṃsa Heaven to preach a sermon, as an act of gratitude, to his mother, who had become a deva, and he was welcomed back to earth with a great festival of lights. Teachers receive the same obeisance, a tradition started by National Schools founded in defiance of the colonial administration and continued after independence by state schools.