瑜伽論記 4.338

4.338

如是一切已下，第三結成聖行。景師釋：問二乘所得四無量是其有漏，云何經說覺分俱行，為釋此疑故。論說云：如是一切雖是有漏唯聖能修，故經宣說此四無量覺分俱行。基師釋：依殊勝行唯聖能修，若無漏者覺分俱時行，若有漏者二乘等起覺分前後有用俱行引覺分，覺分由此亦名聖行。

From "All such as these" below: the third part concludes with the establishment of noble practice. Master Jing explains: Question: The four immeasurables attained by the two vehicles are tainted; why does the sūtra say they are conjoined with the factors of awakening? In order to resolve this doubt, the treatise says: "Although all such as these are tainted, they can only be cultivated by noble ones; therefore, the sūtra declares that these four immeasurables are conjoined with the factors of awakening." Master Ji explains: Relying on superior practice, only noble ones can cultivate them. If they are taintless, they operate simultaneously with the factors of awakening; if they are tainted, when the two vehicles and others arouse them, they are effective before and after the factors of awakening, operating together to induce the factors of awakening. On this basis, the factors of awakening are also called noble practice.