大乘起信論義記 3.131

3.131

It is like the nature of fire within wood, which is the correct cause of fire; if no person knows it and does not employ skillful means, for it to be able to burn the wood by itself is impossible. Sentient beings are also like this: although they possess the power of the perfuming of the correct cause, if they do not encounter the conditions of Buddhas, bodhisattvas, spiritual friends, and so forth, for them to be able to sever afflictions and enter nirvāṇa by themselves is impossible. Even if there is the power of external conditions, if the pure dharma within does not yet possess the power of perfuming, they likewise cannot ultimately feel revulsion toward the suffering of birth-and-death and happily seek nirvāṇa.