四分比丘戒本疏 2.62

2.62

Thirty-third: the precept against eating in a separate group. This means that within various boundaries, whether natural or established by legal procedure, whether large or small, within the same boundary one excludes monks to receive a separate invitation or to beg separately for food. At such an eating place, where there are four or more persons, they exclude other monks, down to even a single person; and if during the proper time they eat the five primary foods, with every swallow they commit the offence of eating in a separate group. If the food is invited for the Saṃgha, four persons eating together do not commit [the offence of] separate eating, because the flavor of the food is identical. According to the intention of the Vinaya's enactment: first, it was feared that wicked persons would form cliques to disrupt the Saṃgha; second, it was feared that if [all] became Saṃgha [gatherings], it would be difficult for the dānapati to provide for them. Therefore, [eating together without offence] is permitted only for three persons or fewer. According to the Prātimokṣa text, there are seven exemptions, which can be expanded to eight, and when fully reasoned out, there are fourteen. As for the seven exemptions: first, 'illness'—this illness is down to having one's heel split so that one cannot walk to keep up with companions; second, 'the time of robe-making', which refers to the one month of the kārttika or within the five months of the kaṭhina robe, which is the time when robes ought to be made; third, 'the time of robe-giving'—this exemption has two kinds, as explained in the preceding precept.