大乘起信論略述 2.134

2.134

論。以垢無量至以為對治　述曰。此顯眾生行之所以也。真如之理既遍一切。無明真有垢染義。即驗垢遍一切法也。故修眾善以為對治。

[Treatise:] Because defilements are immeasurable... takes them as antidotes.
[Exposition:] This reveals the reason for sentient beings' practice. Since the principle of suchness pervades all, and avidyā genuinely has the quality of defilement, this confirms that defilement pervades all phenomena. Therefore, one cultivates myriad goods as antidotes.