法苑珠林 24.49

24.49

又涅槃經云。若離四法得涅槃者。無有是處。何等為四。一親近善友二專心聽法。三繫念思惟。四如法修行。以是義故。聽法因緣。則得近於大般涅槃。何以故。開法眼故。世有三人。一者無目（譬凡夫人）二者一目（譬聲聞人）三者二目（譬諸菩薩）言無目者。常不聞法。一目之人雖暫聞法其心不住。二目之人專心聽受如聞而行。以聽法故得知世間如是三人。

Furthermore, the Nirvāṇa Sūtra states: “If one could attain nirvāṇa apart from four things, that would be impossible. What are the four? First, drawing near to good friends. Second, single-mindedly listening to the Dharma. Third, focused contemplation. Fourth, practicing in accordance with the Dharma. For this reason, through the condition of listening to the Dharma, one draws close to Mahāparinirvāṇa. Why is this? Because it opens the Dharma eye. There are three kinds of people in the world: the first is without eyes (a metaphor for ordinary persons); the second has one eye (a metaphor for śrāvakas); the third has two eyes (a metaphor for bodhisattvas). One 'without eyes' never hears the Dharma. A person with 'one eye', although hearing the Dharma for a short while, their mind does not abide in it. A person with 'two eyes' single-mindedly listens and receives it, and practices as heard. It is through hearing the Dharma that one comes to know these three kinds of people in the world.”