Campeyyajātaka

Suttapiṭaka · Khuddakanikāya · Jātaka (1) · Vol. 27 · Section 2185

[2185] Even a city could the nāga reduce to ashes— for thus is he endowed with strength and energy (vīriya); yet the nāga, revering the Dhamma, therefore, exerting himself, practices austerity (tapa).

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.