首楞嚴義疏注經 10.38

10.38

此人觀中以四大為所觀處，觀成能知四萬劫中眾生生滅，咸皆體常。以眾生皆以四大為體，四大既常，眾生亦常，故無散失。

In this person's contemplation, the four great elements are taken as the object of contemplation. When the contemplation is accomplished, he is able to know that the arising and ceasing of sentient beings over forty thousand eons are all permanent in substance. Because sentient beings all have the four great elements as their substance, and since the four great elements are permanent, sentient beings are also permanent, and therefore there is no dispersion or loss.