俱舍論記 23.46

23.46

「如是四種至獨是上品」者，釋第二句。四皆是修，非是聞、思，唯等引故。雖同修攝，四中前二是下品攝，以俱可動、猶可退故。忍中品攝，勝前煖、頂二善根故，有後第一為其上故，所以名中。世第一法獨是上品，由三品不同，故分四種。若論煖、頂、忍位不同，皆有三品，此中且據束九為三攝四善根。若依《正理》，由下、中、上及上上品分為四種。又《婆沙》第六云「答：總有三品，謂下、中、上，煖是下品，頂是中品，忍及世第一法是上品。」廣如彼說。

Regarding 'These four kinds... is uniquely of the superior grade': this explains the second pāda. All four are attainment through cultivation (bhāvanā-mayī), not through hearing (śrutamayī) or reflection (cintāmayī), because they are solely equipoised (samāhita). Although equally subsumed under cultivation, among the four, the first two are subsumed under the inferior grade, because both are unstable and can still be fallen away from. Forbearance is subsumed under the middling grade, because it is superior to the two previous roots of good, Heat and Summits, and has the subsequent Supreme [Dharmas] above it; hence it is called middling. Worldly supreme dharmas are uniquely of the superior grade. Due to the differences among the three grades, they are divided into four kinds. If one discusses the differences among the stages of Heat, Summits, and Forbearances, each has three grades; here, it is provisionally based on bundling the nine into three to subsume the four roots of good. According to the Nyāyānusāra, they are divided into four kinds by inferior, middling, superior, and superior-superior. Furthermore, the Vibhāṣā (fascicle 6) says: 'Answer: In total there are three grades, namely inferior, middling, and superior; Heat is the inferior grade, Summits are the middling grade, and Forbearances and worldly supreme dharmas are the superior grade' (as explained at length there).