俱舍論疏 29.46

29.46

論「八中前三至想觀增故」，述前三體。前三以無貪為體者，以近治貪故。然契經中說內有色想觀外色者，非是以想慧為體，以於此時想觀增故。如四念住及宿住念等，實慧為體而說念也。若慧為體，應近治廢。

The passage of the treatise starting with "Among the eight, the first three... until: because ideation and contemplation are prominent" explains the essence of the first three. That the first three have non-greed as their essence is because they directly counteract greed. However, when the sūtra speaks of 'possessing the notion of internal form, one contemplates external forms', it does not mean that they have ideation and discernment (prajñā) as their essence, but rather that at this time ideation and contemplation are prominent. Just as with the four applications of mindfulness (smṛtyupasthāna) and the recollection of past lives (pūrvanivāsānusmṛti), which actually have wisdom as their essence and yet are called mindfulness. If wisdom were their essence, the direct counteragent would be abolished.