俱舍論記 25.59

25.59

「於此三中至已得德故」者，釋下兩句。於三退中，世尊唯有最後一種受用退也，以具眾德無容一時頓現前故。隨一現前、餘不現前，名受用退。餘利不動阿羅漢、獨覺，於三退內有後受用。中未得退，亦於勝己不共佛法殊勝功德猶未得故。釋利中後已得功德必不退故，無已得退。餘五種姓容具有三，以鈍根故。亦容退失已得德，故釋鈍三。

"Among these three... because of already attained virtues" explains the lower two lines. Among the three kinds of falling away, the World-Honoured One has only the last kind, falling away from experiential enjoyment, because, possessing all virtues, there is no possibility of them all being manifested at once. When any one is manifested and the others are not manifested, this is called falling away from experiential enjoyment. The other, keen-facultied immovable arhats and pratyekabuddhas have, among the three kinds of falling away, the latter [falling away from] experiential enjoyment, and the intermediate falling away from what has not yet been attained, because they also have not yet attained the supreme virtues of the unique buddha-dharmas that surpass themselves. This explains that for the keen-facultied, with respect to the intermediate and the latter, their already attained virtues definitely never fall away, and hence they have no falling away from what has been attained. The other five lineages may possess all three, because they are dull-facultied. They can also fall away from already attained virtues, which explains "the dull have three."