十不二門指要鈔 2.119

2.119

初、結指心因。指上果人三業真應互融，雖即難思，豈過百界？百界融泯全在我心。因心若無，果須造得，若信因果相稱，方知三密有本。他云，信下無因果字。有亦未多，令義易顯，故須存之。

First, concluding by pointing to the mental cause. Pointing to the mutual fusion of the three karmas and the true and responsive of the fruition person above: although inconceivable, how could they exceed the hundred realms? The fusion and obliteration of the hundred realms reside entirely in our mind. If they were absent in the causal mind, the fruit would have to be newly created; if one believes that cause and effect correspond to each other, only then does one know that the three secrets have a root. Others say that there are no characters for 'cause and effect' below 'believes'. Even if there are, they are not superfluous, and they make the meaning easy to understand, so they must be retained.