法苑珠林 42.18

42.18

又長阿含經云。佛命阿難。吾渴欲飲。汝取水來。阿難白言。向有五百乘車。於上流渡。水濁未清。可以洗足。不中飲也。如是三勅阿難。汝取水來。阿難白言。今拘孫河去此不遠。清冷可飲。亦可澡浴。時有鬼神居在雪山。篤信佛道。即以鉢盛八種淨水奉上世尊。佛為愍彼故為受之。

Furthermore, the Dīrgha-āgama states: 'The Buddha commanded Ānanda: "I am thirsty and wish to drink; fetch water." Ānanda addressed the Buddha: "Just now five hundred carts crossed upstream; the water is turbid and not yet clear; it may be used to wash feet, but is not fit to drink." In this manner, he commanded Ānanda three times: "Fetch water." Ānanda addressed the Buddha: "The Kakutsthā River is now not far from here; it is clear and cool, fit to drink, and also fit to bathe in." At that time, there was a spirit dwelling in the Snow Mountains who had earnest faith in the Buddha's Way; he immediately filled an alms bowl with eight kinds of pure water and presented it to the World-Honoured One. The Buddha, out of pity for him, accepted it for his sake.'