大唐西域記 6.16

6.16

伽藍東六七十步，有一精舍，高六十餘尺，中有佛像，東面而坐。如來在昔，於此與諸外道論議。次東有天祠，量等精舍。日旦流光，天祠之影不蔽精舍；日將落照，精舍之陰遂覆天祠。

These three ditches are unfathomable in their depth; when the floods of summer and autumn fill all the lakes and ponds with water, these deep caverns show no signs of the water standing in them. East of the sangharama 60 or 70 paces is a vihara about 60 feet high. There is in it a figure of Buddha looking to the east in a sitting posture. When Tathagata was in the world in old days, he discussed here with the heretics. Farther east is a Deva temple of equal size with the vihara. When the sun is rising, the Deva temple does not cast its shade on the vihara, but when it is setting, the vihara obscures the Deva temple. Three or four li to the east of the vihara "which covers with its shadow" is a stupa. This is where Sariputra discussed with the heretics. When Sudatta first bought the garden of the Prince Jeta for the purpose of building a vihara for Buddha, then Sariputra accompanied the nobleman to inspect and assist the plan. On this occasion six masters of the heretics sought to deprive him of his spiritual power. Sariputra, as occasion offered, brought them to reason and subdued them. There is a vihara by the side, in front of which is built a stupa; this is where Tathagata defeated the heretics and acceded to the request of Visakha.