摩訶止觀 4.13

4.13

小乘明義，無作戒即是第三聚；大乘中《法鼓經》但明色、心，無第三聚。心無盡故，戒亦無盡。若就律儀戒論，無作可解。「定共戒無作」者，與定俱發。有人言：「入定時有，出定時無。」有人言：「無作依定，定在不失，定退即謝也。」「道共戒無作」者，此無作依道，道無失故，此戒亦無失。戒定、道共，通是戒名說，通以性戒為本。故經云：「依因此戒，能生禪定及滅苦智慧。」即此意也。

The Hīnayāna explains the meaning by taking unmanifest precept as the third category [neither form nor mind]; in the Mahāyāna, the Mahābherīhāraka-sūtra explains only form and mind, without a third category. Because mind is inexhaustible, the precepts are also inexhaustible. If discussed in terms of the precepts of restraint (saṃvara-śīla), the unmanifest is understandable. The 'unmanifest precept co-arising with concentration' arises together with concentration. Some say: 'It exists when entering concentration and is absent when emerging from concentration.' Others say: 'The unmanifest relies on concentration; as long as concentration is present it is not lost, but when concentration declines it fades away.' As for the 'unmanifest precept co-arising with the way', this unmanifest relies on the way; because the way is never lost, this precept is also never lost. The precepts co-arising with concentration and with the way are both spoken of under the name of 'precepts', and both take natural morality as their root. Thus the sūtra says: 'Relying on this precept, one can give rise to meditative concentration and to wisdom that extinguishes suffering.' This is the meaning.