首楞嚴義疏注經 10.35

10.35

In superior samādhi, taking the two dharmas of mind and objects as what is exhaustively investigated, because of this contemplation's completion, he knows that the arising and ceasing of sentient beings in the ten directions over twenty thousand eons cycle without ever dispersing or being lost, like water turning to ice and ice returning to water: although cycling, their essence is not lost; hence he takes it to be permanent.