俱舍論記 25.124

25.124

「謂出觀位至及所乘乘」者，答。此中兩解，前解可知。後解云：或此四種，佛如導師、法如道路、僧如商侶、戒如所乘乘。

Regarding "That is, at the time of emerging from contemplation [...] and the vehicle ridden": this is the answer. In this there are two explanations; the first explanation can be understood from the text. The second explanation says: alternatively, of these four kinds, the Buddha is like a guide, the Dharma is like the road, the Saṃgha is like fellow merchants, and morality is like the vehicle that is ridden.