俱舍論記 15.129

15.129

「聖說此中至說名不動」者，答。等謂等取喜、樂二受。故《正理》云「聖說：此中有尋、伺、喜、樂受動故。由下初定有尋、伺動，由下二定有喜受動，由下三定有樂受動。以有尋等，災患未息，故立動名。若《不動經》中，據因能感不動果故，說名不動。又解：等取喜、樂，出、入息，隨其所應說名為動。

Regarding 'The Noble One said that here ... to ... is called immovable': this is the reply. 'And so forth' includes the two feelings of joy (prīti) and pleasure (sukha). Therefore the Nyāyānusāra states: 'The Noble One said: Here, there is movement due to vitarka, vicāra, and the feelings of joy and pleasure.' Due to the lower first dhyāna having movement from vitarka and vicāra, due to the lower second dhyāna having movement from the feeling of joy, and due to the lower third dhyāna having movement from the feeling of pleasure. Because of having vitarka and so on, calamities have not yet ceased, and thus it is designated with the name 'movable'. But in the Āneñja-sūtra, it is called 'immovable' based on the fact that the cause is capable of producing an immovable fruit. Another explanation: 'and so forth' includes joy, pleasure, and in-and-out breaths, which are called 'movement' as appropriate.