大方廣圓覺修多羅了義經略疏 2.186

2.186

於一味淨覺之中，說輪迴本末、種性差別、雜染等法而無乖失，故不思議。

In the midst of the single flavor of pure enlightenment, expounding the root and branch of saṃsāra, the distinctions of nature-lineage, defiled phenomena, and so forth, yet without any contradiction or error; therefore it is inconceivable.