大比丘三千威儀 1.38

1.38

There are also five matters: first, one should mindfully apply oneself to studying wisdom; second, one should contemplate the eradication of the three poisons; third, one should contemplate seeking the essential Way; fourth, seeing grass growing on the stūpa, one should mindfully remove it with the hands, but must not seize and pull it roughly; fifth, seeing any impurity, one should promptly remove it.