肇論新疏 2.207

2.207

是以般若之與真諦，言用即同而異（初句），言寂即異而同（次句）。同故，無心於彼此（釋）；異故，不失於照功。

Therefore, regarding prajñā and the ultimate truth, spoken of in terms of function they are identical yet distinct (the first phrase); spoken of in terms of stillness they are distinct yet identical (the second phrase). Because they are identical, there is no mind toward this or that (explanation); because they are distinct, they do not lose the efficacy of illumination.