[37] Bhikkhus, a bhikkhu who possesses four qualities is incapable of decline and is in the very presence of Nibbāna. Which four? Here, bhikkhus, a bhikkhu is accomplished in virtue (sīla), guards the doors of the sense faculties (indriya), knows moderation in eating, and is devoted to wakefulness.
And how, bhikkhus, is a bhikkhu accomplished in virtue? Here, bhikkhus, a bhikkhu is virtuous; he dwells restrained by the restraint of the Pātimokkha, accomplished in conduct and resort, seeing danger in the slightest faults; having undertaken the training rules, he trains in them. Thus, bhikkhus, is a bhikkhu accomplished in virtue.
And how, bhikkhus, does a bhikkhu guard the doors of the sense faculties? Here, bhikkhus, having seen a form with the eye, a bhikkhu does not grasp at its sign (nimitta) nor grasp at its details (anubyañjana). Since, if he dwelt with the eye faculty unrestrained, evil, unwholesome states of covetousness and grief might flow in upon him, he practises for its restraint; he guards the eye faculty, he attains restraint over the eye faculty. Having heard a sound with the ear … having smelt an odour with the nose … having tasted a flavour with the tongue … having touched a tangible object with the body … having cognized a mental phenomenon with the mind, he does not grasp at its sign nor grasp at its details. Since, if he dwelt with the mind faculty unrestrained, evil, unwholesome states of covetousness and grief might flow in upon him, he practises for its restraint; he guards the mind faculty, he attains restraint over the mind faculty. Thus, bhikkhus, does a bhikkhu guard the doors of the sense faculties.
And how, bhikkhus, does a bhikkhu know moderation in eating? Here, bhikkhus, reflecting wisely, a bhikkhu takes his food neither for amusement, nor for intoxication, nor for adornment, nor for beautification, but only for the maintenance and sustenance of this body, for the ending of affliction, and for assisting the holy life, considering: "Thus I shall put an end to the old feeling (vedanā) and not arouse a new feeling; and there will be for me continuance, blamelessness, and dwelling in comfort." Thus, bhikkhus, does a bhikkhu know moderation in eating.
And how, bhikkhus, is a bhikkhu devoted to wakefulness? Here, bhikkhus, during the day a bhikkhu purifies his mind (citta) of obstructive states by walking back and forth and by sitting; in the first watch of the night he purifies his mind of obstructive states by walking back and forth and by sitting; in the middle watch of the night he lies down in the lion's posture on his right side, placing one foot upon the other, mindful and clearly comprehending, having attended to the perception of rising; in the last watch of the night, having risen, he purifies his mind of obstructive states by walking back and forth and by sitting. Thus, bhikkhus, is a bhikkhu devoted to wakefulness.
Bhikkhus, a bhikkhu who possesses these four qualities is incapable of decline and is in the very presence of Nibbāna.
A bhikkhu established in virtue,
restrained in the sense faculties,
knowing moderation in eating,
and devoted to wakefulness—
dwelling thus, ardent (ātāpī),
untiring by day and by night,
developing wholesome dhamma
for the attainment of security from bondage—
a bhikkhu who delights in heedfulness,
or who sees danger in heedlessness,
is incapable of decline
and is in the very presence of Nibbāna.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.