摩訶止觀 4.193

4.193

復次，重說欲者，欲從二邊正入中道。不雜二邊為「精」；任運流入為「進」。繫緣法界，一念法界為「念」。修中觀方便名「善巧」。息於二邊，心水澄清，能知世間生滅法相；不二其心，清淨常一，能見般若也。

Furthermore, to explain desire once more: it is desiring to enter directly into the middle way from the two extremes. Not being mixed with the two extremes is 'vigor'; flowing naturally into it is 'advancement.' Fastening conditions to the dharmadhātu and having a single thought of the dharmadhātu is 'mindfulness.' Cultivating expedients of the middle contemplation is called 'skillfulness.' Quelling the two extremes, the water of the mind is clear and calm, able to know the marks of the arising and ceasing of worldly phenomena; not dividing one's mind, pure and constantly unified, one is able to see prajñā.