佛祖統紀 30.38

30.38

When it increases to seven hundred years, the sixteen arhats will have finished propagating the Dharma (from their descent into the human world until then should be five thousand years of preaching and converting). Gathering all the scriptures and relics, they will erect a stūpa. Sitting cross-legged, they will encircle this stūpa, and all will sink into the earth. This marks the appearance of the complete extinction of the Buddha's Dharma. From then on, one hundred billion pratyekabuddhas will appear in the world to preach the Dharma and benefit sentient beings (The Scripture on the Total Extinction of the Dharma. Note: The Record of the Duration of the Dharma states that when human lifespan reaches seventy thousand years, the sixteen arhats will build a stūpa of the seven treasures, and Śākyamuni's bodily dhātus will all be collected within it. Making offerings of incense and flowers, they will speak thus: "Having previously received the command to protect and uphold the true Dharma and to bring manifold benefits to gods and humans, now that the treasury of the Dharma is submerged and our conditions [with beings] are completed, we now bid farewell and enter extinction." Through their prior vow and power of concentration, fire will rise and burn their bodies. The stūpa will then sink into the earth down to the diamond boundary. At that time, Śākyamuni's true Dharma will be forever extinguished. Thenceforth, seven hundred koṭis of pratyekabuddhas will appear in the world at one time. When human lifespan reaches eighty thousand years, the holy assembly of pratyekabuddhas will again all enter extinction. Thereafter, Maitreya Tathāgata will appear in the world. The Record speaks of eternal extinction at seventy thousand, which is too far removed from the Final Dharma period. Now we take the scripture's statement of seven hundred years as correct).