淨名經集解關中疏 2.393

2.393

"Ānanda, there are these four māras and eighty-four thousand gates of defilements, by which sentient beings are wearied and toiled; the Buddhas use precisely these dharmas to perform the Buddha's work." Sengzhao says: "The three poisons in equal parts—these are the roots of the four māras and defilements. From each single root twenty-one thousand defilements arise, totaling eighty-four thousand. Because they produce immeasurable defilements, they are called 'gates'. Sentient beings all consider defilements to be illnesses, yet the Buddhas use them as medicine. Just as when a courtesan's lust was a problem, [the Buddha] pushed her passions to the limit and only then did she awaken to the Way; and when a poisonous dragon's anger was inevitably a problem, he further intensified its wrath. This is removing lust by means of lust, and removing anger by means of anger, just as a good physician removes poison by means of poison. Such is the boundless versatility of the Buddha's work."