[213] On one occasion the Blessed One was dwelling among the Sakyans, at a town of the Sakyans named Devadaha. There the Blessed One addressed the bhikkhus: "Bhikkhus, I do not say of all bhikkhus that there is work to be done with diligence (appamāda) regarding the six bases of contact (phassāyatana); yet neither, bhikkhus, do I say of all bhikkhus that there is no work to be done with diligence regarding the six bases of contact.
Those bhikkhus, bhikkhus, who are arahants, whose taints (āsava) are destroyed, who have lived the holy life, done what had to be done, laid down the burden, reached their own true goal, utterly destroyed the fetters of existence, and are liberated by final knowledge — of those bhikkhus, bhikkhus, I say that there is no work to be done with diligence regarding the six bases of contact. For what reason? What [need] have they of diligence? They are incapable, by that, of being negligent.
But those bhikkhus, bhikkhus, who are trainees (sekha), who have not attained their mind's ideal, who dwell aspiring to the unsurpassed security from bondage (yogakkhema) — of those bhikkhus, bhikkhus, I say that there is work to be done with diligence regarding the six bases of contact. For what reason? There are, bhikkhus, forms cognizable by the eye that are delightful and also undelightful. Though these touch him again and again, they do not persist overwhelming his mind (citta); when the mind is not overwhelmed, energy (vīriya) is aroused and unflagging, mindfulness (sati) is established and unmuddled, the body is tranquil and undisturbed, the mind is concentrated and one-pointed. Seeing this fruit of diligence, bhikkhus, I say of those bhikkhus that there is work to be done with diligence regarding the six bases of contact. …
There are, bhikkhus, tastes cognizable by the tongue that are delightful and also undelightful. Though these touch him again and again, they do not persist overwhelming his mind; when the mind is not overwhelmed, energy is aroused and unflagging, mindfulness is established and unmuddled, the body is tranquil and undisturbed, the mind is concentrated and one-pointed. Seeing this fruit of diligence, bhikkhus, I say of those bhikkhus that there is work to be done with diligence regarding the six bases of contact. …
There are, bhikkhus, mental phenomena (dhammā) cognizable by the mind that are delightful and also undelightful. Though these touch him again and again, they do not persist overwhelming his mind; when the mind is not overwhelmed, energy is aroused and unflagging, mindfulness is established and unmuddled, the body is tranquil and undisturbed, the mind is concentrated and one-pointed. Seeing this fruit of diligence, bhikkhus, I say of those bhikkhus that there is work to be done with diligence regarding the six bases of contact."
The first [sutta].
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.