十不二門指要鈔 2.129

2.129

初、標者，從諭立也。能受者即三草二木、七方便眾生，能潤者即大雲注雨，即前四時三教。今經開之，唯一地所生、一雨所潤，無復差降，名為不二。觀己心地三千與佛心地三千不殊，則念念受潤常沾妙益，依此為門，則成二妙。

First, the heading is established from a metaphor. Those able to receive are the three grasses and two trees, the sentient beings of the seven expedient means; that able to moisten is the great cloud pouring down rain, which refers to the previous four periods and three teachings. Now this sūtra opens them so that there is only that produced from the single ground and moistened by the single rain, without any further differences or gradations; hence it is called nondual. Contemplating the three thousand of one's own mind-ground as not different from the three thousand of the Buddha's mind-ground, then thought-moment by thought-moment one receives moisture and constantly receives the wondrous benefit. Relying on this as a gate, it constitutes the two subtleties.