首楞嚴義疏注經 1.46

1.46

This cites the number. When the Buddha first attained the Way, he first delivered the five people including Kauṇḍinya; next he delivered the three Kāśyapa brothers together with their disciples, totalling one thousand; next he delivered Śāriputra and Maudgalyāyana, each with one hundred disciples; next he delivered fifty people including the elder Yaśas. The sūtra gives the large round number, hence omitting the five people. This assembly previously served heterodox ways together, toiling bitterly for accumulated kalpas without the slightest attainment; as soon as they met the Buddha, they immediately attained the superior fruit. Feeling the Buddha's kindness deeply, they always followed the Buddha's conversion, serving as the constant accompanying assembly.