瑜伽師地論略纂 15.160

15.160

論云「若以猛利貪欲、瞋恚等纏發起，名因緣重」者，要由先業道中貪等發業，方因緣重。若非猛利，非業所攝，不善根發，思輕也。

Regarding the treatise's statement, "If initiated by intense entanglements of covetousness, anger, and so forth, it is called heavy by virtue of cause and condition": only when greed and so forth in the previous courses of action initiate karma is it heavy by virtue of cause and condition. If it is not intense, it is not subsumed under karma; when initiated by unwholesome roots, the intention is light.