四分律行事鈔資持記 3.821

3.821

正示中，初文，前敘道俗相資。修道緣者，假彼外護故。生善境，福智由生故。出家下，次明互相敬護。初道須攝俗。四輩，即天人龍鬼。幽通三趣，顯則唯人。

Under direct instruction, the first text: first, it describes the mutual reliance between monastics and laypeople. 'Conditions for cultivating the Path' refers to relying on their external protection; 'realms where goodness arises' is because merit and wisdom arise from them. 'The renunciant...' onwards next explains mutual reverence and protection. First, the monastic must gather in the laity. The 'four classes' refers to devas, humans, nāgas, and ghosts; in the unseen, it extends to three destinies, but manifestly, it is humans alone.