大般涅槃經集解 36.27

36.27

案寶亮曰：天竺云阿浮多達磨也。夫希有之事，名未曾有。如大青牛，行瓦鉢間，令諸瓦鉢互相棠觸，無所傷損。如此等事，悉名未曾有經。

Baoliang states: In India it is called adbhutadharma. Rare events are called “unprecedented.” For instance, a great black ox walking among earthenware bowls causes the earthenware bowls to knock against one another without incurring any damage. Events such as these are all called adbhutadharma sūtras.