六祖大師法寶壇經 1.72

1.72

師示眾云：「善知識！何名坐禪？此法門中，無障無礙，外於一切善惡境界，心念不起，名為坐；內見自性不動，名為禪。善知識！何名禪定？外離相為禪，內不亂為定。外若著相，內心即亂；外若離相，心即不亂。本性自淨自定，只為見境，思境即亂。若見諸境心不亂者，是真定也。善知識！外離相即禪，內不亂即定。外禪內定，是為禪定。《菩薩戒經》云：『我本元自性清淨。』善知識！於念念中，自見本性清淨，自修自行，自成佛道。」

The Master instructed the assembly, saying: "Good friends! What is called sitting in meditation (zuochan)? In this Dharma gate, unobstructed and unhindered, outwardly, in the face of all good and bad sense-realms, thoughts in the mind do not arise—this is called 'sitting'. Inwardly, seeing the svabhāva unmoved—this is called 'meditation' (chan). Good friends! What is called chan-samādhi (dhyāna-samādhi)? Outwardly being free of marks is chan; inwardly not being disordered is samādhi. Outwardly, if one clings to marks, the mind within is immediately disordered; outwardly, if one is free of marks, the mind is immediately not disordered. The original nature is naturally pure and naturally in samādhi; it is only because of seeing sense-realms that thinking about sense-realms immediately causes disorder. If one sees all sense-realms and the mind is not disordered, this is true samādhi. Good friends! Outwardly being free of marks is chan; inwardly not being disordered is samādhi. Chan outwardly and samādhi inwardly: this is chan-samādhi. The Bodhisattva Precepts Sūtra says: 'My original svabhāva is fundamentally pure.' Good friends! In thought after thought, see your original nature as pure for yourself, cultivate for yourself, practice for yourself, and attain the Buddha Way for yourself."