佛說處處經 1.53

1.53

The Buddha and the arhats both practice the teachings of the thirty-seven factors of awakening. It is like the flame of a lamp: the Buddha investigates and knows how many elements there are, knows their roots and branches, guards against them, and extinguishes them; an arhat does not investigate the roots and branches, but simply extinguishes them directly. The Buddha is like one who follows a tree from its trunk to its branches, knowing and distinguishing them; an arhat's practice is like going from the branches to the trunk. One who goes from the trunk to the branches realizes that the root is empty; one who does not know emptiness does not attain the Way.