[1660] Bhikkhus, do not think evil, unwholesome thoughts — that is: a thought of sensuality (kāmavitakka), a thought of ill will (byāpādavitakka), a thought of harming (vihiṃsāvitakka). For what reason? Because these thoughts, bhikkhus, are unbeneficial, do not belong to the fundamentals of the holy life, and do not lead to disenchantment (nibbidā), to dispassion (virāga), to cessation, to peace, to direct knowledge (abhiññā), to full awakening, to Nibbāna. But when you think, bhikkhus, you should think: 'This is suffering (dukkha)'; you should think: 'This is the origin of suffering'; you should think: 'This is the cessation of suffering'; you should think: 'This is the way of practice leading to the cessation of suffering.' For what reason? Because these thoughts, bhikkhus, are beneficial; these belong to the fundamentals of the holy life; these lead to disenchantment, to dispassion, to cessation, to peace, to direct knowledge, to full awakening, to Nibbāna. Therefore, bhikkhus, effort should be made [to understand]: 'This is suffering' … 'This is the way of practice leading to the cessation of suffering': effort should be made.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.