俱舍論頌疏論本 24.93

24.93

無聞無緣下者，此明無色無見道也，謂無色中無正聞故。又無色界不緣下欲界故。夫入見道，要須聞教及緣欲苦，無色不然，故無見道。

"No hearing, no objectifying the lower": this explains that the formless realm lacks the path of seeing, meaning that in the formless realm there is no correct hearing. Moreover, the formless realm does not take the lower desire realm as an object. In entering the path of seeing, one must hear the teaching and take the suffering of desire as an object; the formless realm is not so, and therefore lacks the path of seeing.