法華義疏 11.15

11.15

略有二種：一、隨喜法；二、隨喜人。隨喜法者，若順此經而生歡喜，即是金剛般若，信心不逆故名隨喜。二、隨前人所作而生歡喜，如見受持此經乃至解說而生歡喜，故名隨喜人。

Briefly, there are two kinds: first, rejoicing in accord with the Dharma; second, rejoicing in accord with persons. Rejoicing in accord with the Dharma means that if one accords with this sūtra and gives rise to joy, this is diamond prajñā; because one's faithful mind is not contrary, it is called rejoicing in accord. Second, giving rise to joy in accordance with what another person does, such as seeing someone uphold this sūtra or even explain it and giving rise to joy, is therefore called rejoicing in accord with persons.