首楞嚴義疏注經 10.348

10.348

湛前行陰，合歸識陰。見識不動，認為真湛。齊此名為識陰邊際。以見行陰是生滅法，離生滅處必是湛寂，就所修處即識分齊也。

Making the preceding aggregate of formations tranquil and uniting it back into the aggregate of consciousness. Seeing consciousness as unmoving, one takes it to be true tranquility. Up to this point is called the boundary of the aggregate of consciousness. Because one sees that the aggregate of formations is a dharma of arising and ceasing, the state free from arising and ceasing must be tranquil and quiet; in terms of where one cultivates, this is the bounds of consciousness.