Triple Purification of the Worlds

Great-Eloquence Bodhisattva wants to see Many-Treasures for himself, and he makes his desire known to Sakyamuni. The Buddha replies:

Many-Treasures Buddha made another great vow: “If any Buddha wishes to show me to the people when my Stupa of treasures appears before him so that I may be able to hear the Lotus Sutra, all his duplicate Buddhas in the worlds of the ten directions must be recalled. Then I will show myself before the people.”

Then Sakyamuni emitted a ray of light from the white curls between his eyebrows. The ray of light illumined the east, where the people saw innumerable Buddhas of innumerable worlds. Illuminated by the ray of light, those Buddhas of the worlds of the ten directions came pouring into the World of Endurance (our world) to make offerings to Sakyamuni Buddha and Many-Treasures Tathagata. At that moment, the World of Endurance was purified. The ground of the world became lapis lazuli; the roads were marked off by golden ropes; all cities, rushing torrents, and mountains (barriers which divide people from each other) were eliminated. Each of the arriving Buddhas was accompanied by an attending Bodhisattva. They all came to the purified World of Endurance, and sat under jeweled trees on lion-like thrones. All the thrones in the one thousand million Sumeru-worlds (inhabited worlds) were too few to accommodate so many Buddhas, so Sakyamuni purified two hundred billion nayuta [one nayuta is one hundred thousand million] other worlds to receive them. Still there was not enough room for them all, so Sakyamuni purified two hundred billion nayuta more worlds in eight directions of space to receive them (p. 183-4).
This is called the “triple purification of the worlds.”

Introduction to the Lotus Sutra