金光明經文句記 2.207

2.207

三、引三文證法身二義。問：前云四喻皆喻應壽能為無量，今何引之證報證法？答：非全法報為應身者，應必斷滅，安能延促不曾休廢？今欲顯示三身融妙，故即以應而證法報。若昧此意，諸大乘對機之身莫能深識。

Third, citing three passages to prove the two meanings of the Dharma body. Question: Earlier it was said that the four metaphors all illustrate that the responsive lifespan can be immeasurable; why are they now cited to prove the reward and Dharma [bodies]? Answer: If it were not the case that the responsive body is completely the Dharma and reward [bodies], the responsive [body] would surely be annihilated; how could it extend or shorten without ever ceasing? Now, wishing to display the subtle integration of the three bodies, he uses the responsive body to prove the Dharma and reward [bodies]. If one is blind to this meaning, no one will be able to deeply know the bodies that respond to capacities in the Mahāyāna.