十不二門指要鈔 2.74

2.74

First, clarifying the reason for nonduality. "Having already realized" raises the stage of those who have already attained realization. That the environment and person of Quiescent Light and Vairocana are nondual derives entirely from the causal virtue of the three thousand realms in a single thought-moment. If they were fundamentally unintegrated in the cause, how could they be unified in the fruit? Even if cultivation were to bring them together, that would still be impermanent and ultimately return to separation.