俱舍論疏 17.65

17.65

論「若先加行至隨二究竟」，三俱轉也。若先加行言非唯遣他，自作亦得。如先作殺加行，後方死等。或先燃火，後燒物等。或先發言，後他解等。如是等類。

The treatise says, "If by prior preparatory action [...] any two reach completion": this is operating together with three. The phrase "prior preparatory action" does not refer only to sending another; performing it oneself is also acceptable. As when one previously performs the preparation for killing, and the death occurs later, etc. Or first lighting a fire, and the object burns later, etc. Or first speaking words, and the other understands later, etc. Examples such as these.