起信論疏筆削記 2.9

2.9

由此下，結指善權，謂論主以一實智，證無分別一味真理，以方便力，為眾生故，善用巧便，而開一味成多法門。多無多相，不違一味，故名善巧。開即演一為多，示即顯令生解也。

From "From this..." onward, it concludes by pointing to the skillful means, meaning that the treatise master, by means of the single real wisdom, realizes the non-differentiating true principle of one flavor, and through the power of expedients, for the sake of sentient beings, skillfully employs expedient means to open the single flavor into multiple Dharma-gates. The multiple have no mark of multiplicity, not violating the single flavor, and are thus called "skillful." "Opening" means expounding the one into many; "demonstrating" means manifesting them so as to generate understanding.