Dasuttarasutta

Suttapiṭaka · Dīghanikāya · Pāthikavagga · Vol. 11 · Section 367

[367] What is the one thing that is of great benefit? Heedfulness (appamāda) with regard to wholesome states (kusalā dhammā). This is the one thing that is of great benefit.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.