[464] 25. "Bhikkhus, these three persons are found existing in the world. Which three? The person whose mind (citta) is like an open sore, the person whose mind is like a flash of lightning, and the person whose mind is like a diamond.
"And which, bhikkhus, is the person whose mind is like an open sore? Here, bhikkhus, a certain person is wrathful and abounding in despair (upāyāsa): even when spoken to but slightly, he takes offence, becomes angry, bears ill will, and turns obstinate; he displays anger, hatred, and displeasure. Just as, bhikkhus, a festering sore, when struck by a stick or a potsherd, discharges its matter all the more, even so, bhikkhus, here a certain person is wrathful and abounding in despair: even when spoken to but slightly, he takes offence, becomes angry, bears ill will, and turns obstinate; he displays anger, hatred, and displeasure. This, bhikkhus, is called the person whose mind is like an open sore.
"And which, bhikkhus, is the person whose mind is like a flash of lightning? Here, bhikkhus, a certain person understands as it really is: 'This is suffering (dukkha)'; he understands as it really is: 'This is the origin of suffering'; he understands as it really is: 'This is the cessation of suffering'; he understands as it really is: 'This is the way of practice leading to the cessation of suffering.' Just as, bhikkhus, a man endowed with sight might see forms in the flash of lightning amid the blinding darkness of night, even so, bhikkhus, here a certain person understands as it really is: 'This is suffering' … he understands as it really is: 'This is the way of practice leading to the cessation of suffering.' This, bhikkhus, is called the person whose mind is like a flash of lightning.
"And which, bhikkhus, is the person whose mind is like a diamond? Here, bhikkhus, a certain person, through the destruction of the taints (āsava), having realized it for himself with direct knowledge, in this very life enters upon and dwells in the taintless liberation of mind (cetovimutti) and liberation by wisdom (paññāvimutti). Just as, bhikkhus, there is nothing a diamond cannot cut, whether gem or rock, even so, bhikkhus, here a certain person, through the destruction of the taints … enters upon and dwells therein. This, bhikkhus, is called the person whose mind is like a diamond.
"These, bhikkhus, are the three persons found existing in the world."
[Editorial footnotes in the Pali source: ¹ In the Po. and Ma. editions the word "iti" is absent. ¹ Yu. reads "seyyathāpi nāma."]
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.