Saṃyutta Nikāya 12

Connected Discourses on Causation

84–93. Exertion, Etc.

“Bhikkhus, one who does not know and see as it really is aging-and-death … volitional formations, their origin, their cessation, and the way leading to their cessation, should make an exertion … arouse a desire … arouse enthusiasm … be unremitting … arouse ardour … apply energy … practise perseverance … practise mindfulness … practise clear comprehension … practise diligence in order to know this as it really is.”