法華經義記 1.63

1.63

「憍梵波提」者，外國名，此間言牛呞比丘。此人雖得羅漢，猶有二事似牛：一者口中空喘、二者其脚跡似牛蹄，常被諸比丘諸譏咲，如來神力接置梵宮，然諸天不咲，故接置天宮，仍說往緣，謂此人昔日五百世常作牛王，是故《無量壽經》言「尊者牛王」，即其人也。

"Gavāmpati" is a foreign name, called here the "ox-chewing monk". Although this person attained arhatship, he still had two traits resembling an ox: first, panting empty-mouthed; second, his footprints resembled ox hooves. Often mocked by the monks, the Tathāgata used supernatural power to convey him to the Brahmā palace. Since the devas would not mock him, he conveyed him to the celestial palace and related his past conditions, stating that in the past, across five hundred lifetimes, this person had constantly been an ox king. For this reason, the Sukhāvatīvyūha Sūtra says "the Venerable Ox King", which refers to this very person.