俱舍論疏 14.134

14.134

論「若作此執至隨行隨作」，論主與餘師出違經過。若謂餘戒有八，齋為第九以為齋體，何故經說離非時食已便作是說此第八支。既言第八，明餘唯七。又言支故，明非別立離非時食以為齋體不是齋支。

The commentary states: "If one adopts this assertion [...] following along in practice and deed", the author of the śāstra points out the fault of contradicting the sūtras to the other masters. If it were held that the other precepts are eight and upavāsa is the ninth serving as the entity of upavāsa, why does the sūtra, after stating 'abstaining from eating at improper times', immediately say 'this is the eighth factor'? Since it says 'eighth', it is clear that the others are only seven. Moreover, because it says 'factor', it is clear that abstaining from eating at improper times is not separately established as the entity of upavāsa to the exclusion of being a factor of upavāsa.