俱舍論記 7.103

7.103

「如是十二至故成二十」者，釋初、後句。《正理》云「無色界無行等事故無威儀路，無攝受支三摩地故亦無通果。」

Regarding "Thus, the twelve ... therefore make twenty": this explains the initial and final lines. The Nyāyānusāra states: "Because in the formless realm there are no actions such as walking, there is no [mind of] deportment; and because there is no samādhi of embracing the limbs [of absorption], there is also no [mind that is] the fruition of supernatural faculties."