大方廣圓覺修多羅了義經略疏 1.595

1.595

此乃能所雙亡即契圓覺，其猶波因水起，波滅水存。幻從覺生，幻滅覺滿。

This means that when both subject and object are forgotten, one accords with perfect enlightenment; it is like waves arising due to water: when the waves cease, the water remains. Illusion arises from enlightenment; when illusion ceases, enlightenment is fulfilled.