金剛經纂要刊定記 3.54

3.54

法喜下二句，對還至本處飯食也。食能資身、法能益心也。思惟假緣對著衣持鉢，忘緣符真對收衣鉢也。乞食既須衣鉢，思惟要假因緣，入定既併資緣，契理須忘念慮。

The two lines beginning "Joy in the Dharma..." correspond to returning to his original place and eating the meal. Food can sustain the body, and the Dharma can benefit the mind. Contemplating provisional conditions corresponds to putting on the robe and holding the bowl; forgetting conditions to accord with the true corresponds to putting away the robe and bowl. Since begging for food requires the robe and bowl, contemplation requires relying on conditions; since entering samādhi requires putting away requisites, tallying with principle requires forgetting discursive thoughts.