俱舍論頌疏論本 17.3

17.3

釋曰：此中三唯道者，此十業道中，貪等三唯道也。業之道故，立業道名，謂貪等相應思說名為業，以彼貪等轉故思轉，彼貪等行故思行，如彼貪等勢力而思有造作故，故貪等三與思為道。

The explanation says: Regarding "among these, three are paths only," among these ten karmapathas, the three such as covetousness are paths only. Because they are the paths of karma, they are given the name karmapatha. That is, volition associated with covetousness and the rest is called karma; because those such as covetousness operate, volition operates, and because those such as covetousness act, volition acts, and because volition performs actions through the power of those such as covetousness, the three such as covetousness are therefore paths for volition.