Dhammapada · 12.3

Attānaṃ ce tathā kayirā, yathāññamanusāsati;Sudanto vata dametha, attā hi kira duddamo.

Attanam ce tatha kayira, yathannamanusasati; Sudanto vata dametha, atta hi kira duddamo.

As one teaches another, so should one do oneself. Well-tamed, one tames others; truly the self is hard to tame.

— Dhammapada 12.3

Source: Pali text from the Khuddaka Nikāya of the Pali Canon (oldest extant Buddhist scripture, compiled c. 3rd century BCE). Public-domain English readings drawn from F. Max Müller's translation in Sacred Books of the East, Vol X (1881) and the Buddhist Publication Society's freely-licensed Acharya Buddharakkhita rendering.