瑜伽論記 5.337

5.337

設行已生，即由此相無有分別者，此釋頌言設諸行已生、由此故無得，謂設於過現已生行中，作前不在內外中間不生之觀。由此觀故尚無分別，不得生於三種雜染。

Regarding "even if formations have already arisen, precisely because of this characteristic there is no conceptual construction": this explains the verse saying, "Even if formations have already arisen, because of this there is nothing attained." This means that even with respect to formations that have already arisen in the past or present, one produces the aforementioned contemplation of their not arising within, without, or in between. Due to this contemplation, conceptual construction does not yet occur, and one cannot give rise to the three kinds of defilement.