Dhammapada · 23.5

Dhanapālo nāma kuñjaro, kaṭukabhedano dunnivārayo;Baddho kabaḷaṃ na bhuñjati, sumarati nāgavanassa kuñjaro.

Dhanapalo nama kunjaro, katukabhedano dunnivarayo; Baddho kabalam na bhunjati, sumarati nagavanassa kunjaro.

The elephant called Dhanapāla, hard to control when in rut, even when bound, eats no morsel — he remembers the elephant forest.

— Dhammapada 23.5

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.