大般涅槃經義記 6.167

6.167

後釋行足從修入證，「行者為生修諸善業」是證方便，「足者見性」是入證矣。「以是」下結。

Afterward, it explains conduct and perfection (caraṇasampanna) as entering realization from cultivation: 'conduct is cultivating all wholesome karmas for the sake of sentient beings' is the expedient means of realization; 'perfection is seeing the nature' is entering realization. From 'for this reason' downward, it concludes.