瑜伽論記 7.283

7.283

言即由如是根力，多修習故，發起四善根者，據行成位，故言發起。基師復云：此中，根力如中邊論，根在煗頂，力在後二位。

Regarding 'it is precisely due to having repeatedly cultivated such faculties and powers that the four wholesome roots are generated': this is based on the stage where practice is accomplished; hence it says 'generated'. Master Ji also says: Here, the faculties and powers are like those in the Madhyāntavibhāga: faculties reside in heat and summit, and powers reside in the latter two stages.