The stepping stone is quite common at the entrance to quite a few 'vihares' in present day Sri Lanka. The 'Moon-stone' was an object of veneration for the adherents of the 'Mahayana' sects in the early days of Buddhism in Sri Lanka. It represented the progressive advancement in the circles of existence till the center of Nirvana was reached. This object of veneration was symbolically degraded as a stone to step on, by the Theravada purists, according to the Mahayanists. But it still survives as an aesthetically pleasing piece of stone sculpture. I saw these two pieces at the Kelaniya Raja Maha Vihara being stepped on, by devotees on the way to the inner sanctum.
