Dhammapada · 22.6

Kuso yathā duggahito, hatthamevānukantati;Sāmaññaṃ dupparāmaṭṭhaṃ, nirayāyūpakaḍḍhati.

Kuso yatha duggahito, hatthamevanukantati; Samannam dupparamattham, nirayayupakaddhati.

As a blade of kusa grass wrongly held cuts the hand, so the spiritual life wrongly grasped drags one to hell.

— Dhammapada 22.6

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.