大乘起信論義記 3.15

3.15

初、緣起體即因也；次、發緣起之由即緣也；後、顯緣起之相，即不染而染也。

First is the essence of pratītyasamutpāda, which is the cause; next is the reason for giving rise to pratītyasamutpāda, which is the condition; finally is revealing the characteristics of pratītyasamutpāda, which is being defiled while undefiled.