金剛經纂要刊定記 3.33

3.33

The commentary's "properly entering samādhi" explains "he spread his seat and sat down" in the sūtra. "Sinking and agitation" and so on: Sinking refers to dullness, which can induce drowsiness and hinder the increase of samādhi. Agitation refers to restlessness; spontaneously grasping at conditions, it can induce distraction and also hinders the mind in samādhi. Furthermore, among the four postures, lying down leads to dullness, walking leads to restlessness, and standing leads to fatigue; only sitting is superior, hence one is free from sinking and agitation. Dullness and restlessness belong solely to ordinary people; as far as the Tathāgata is concerned, he has none of these things, but in bequeathing a standard model now, it is entirely for the sake of posterity. Some may say: "The sūtra only says spreading the seat; how do we know he entered samādhi?" Therefore, the subsequent explanation says that the Wei translation and others make it known that he entered samādhi.