瑜伽論記 7.517

7.517

於無散亂品者，謂汝於先散心取境過去盡滅四無色蘊，及今作觀行時中間失念取相尋思隨煩惱境四無色蘊，汝應於此以聞思心如理思推，此四蘊性是誑幻率爾現前多諸過患不可保信，如是名為於外修受心法觀。泰云：內念住心用勝外念住，不緣五欲名無散亂。

Regarding "the side of non-distraction": it refers to the four formless aggregates that in the past ceased when you previously took objects with a distracted mind, as well as the four formless aggregates of the domain of marks, conceptual investigations, and secondary afflictions grasped when mindfulness was lost in the interim while performing contemplative practice now; regarding these, you should rationally deliberate with a mind of hearing and reflection that the nature of these four aggregates is deceptive and illusory, arising abruptly, having many faults, and cannot be trusted. This is called externally cultivating the contemplation of feelings, mind, and dharmas. Tai says: the mental application of internal mindfulness-dwelling is superior to external mindfulness-dwelling; not taking the five desires as focal objects is called non-distraction.