高僧傳 8.64

8.64

時有沙門法紹，業行清苦，譽齊於度，而學解優之。故時人號曰「北山二聖」。

At that time there was a śramaṇa named Fashao, whose pure and austere practice and reputation were equal to those of Fadu, and whose doctrinal understanding was even superior to his. Therefore, the people of the time called them the "Two Sages of the Northern Mountain."