成唯識論述記 5.256

5.256

述曰：欲緣從來未合事故，此恒緣合境常是我故。若憶過、未而起希望，已合即念；未合即欲，五十五說於所愛事有欲生故。若爾，諸佛應無有欲，無未合事故。今說非佛言未遂合，非說於佛有未合事，故不相違。下諸心所皆准此釋。又欲但觀所樂事轉，所樂之事名末遂合，故此無欲。文與前別，與第八識所簡乃同。

The Commentary states: Desire grasps an object with which one has never yet been united, whereas this [seventh consciousness] constantly grasps an already united object, as it is perpetually [taken to be] the self. If one recollects the past or future and gives rise to hope: what has already been united is [the object of] mindfulness, and what has not yet been united is [the object of] desire, for Fascicle 55 [of the Yogācārabhūmi-śāstra] states that desire arises with respect to a loved object. If that were so, the Buddhas would lack desire, because there is no object with which they have not yet been united. Here we are speaking of non-Buddhas when saying 'not yet having attained union', not saying that there are objects with which the Buddhas have not yet united; therefore there is no contradiction. The mental factors below should all be explained according to this model. Moreover, desire operates only in viewing desired objects; an object of desire is called 'not yet attained in union'; hence this [consciousness] lacks desire. Although this text differs from the earlier one, what it eliminates is identical to that of the eighth consciousness.