首楞嚴義疏注經 2.654

2.654

破離空離水也。離空有流，空且無外，何離之有？若離水有，水外求波，故應非理。流既無生，行陰元寂。

Refuting being apart from space and apart from water. If apart from space there were a flow, space moreover has no outside, so how could there be separation from it? If it existed apart from water, seeking waves outside of water would thus be irrational. Since the flow has no arising, the aggregate of mental formations is originally tranquil.