On one occasion the Blessed One was dwelling at Sāvatthī in Jeta’s Grove, Anāthapiṇḍika’s Park. There the Blessed One addressed the bhikkhus: “Bhikkhus!”
“Venerable sir!” those bhikkhus replied. The Blessed One said this:
“Bhikkhus, a bhikkhu who is not skilled in the ways of others’ minds [should train]: ‘I will be skilled in the ways of my own mind.’ It is in this way that you should train yourselves.
“And how is a bhikkhu skilled in the ways of his own mind? It is just as if a woman or a man, young, youthful, and fond of ornaments, would look at their own facial reflection in a clean bright mirror or in a bowl of clear water. If they see any dust or blemish there, they will make an effort to remove it. But if they do not see any dust or blemish there, they will be glad about it; and their wish fulfilled, they will think, ‘How fortunate that I’m clean!’ So too, self-examination is very helpful for a bhikkhu [to grow] in wholesome qualities.
“[One should ask oneself:] (1) ‘Am I often given to longing  or without longing? (2) Am I often given to ill will or without ill will? (3) Am I often overcome by dullness and drowsiness or free from dullness and drowsiness? (4) Am I often restless or calm? (5) Am I often plagued by doubt or free from doubt? (6) Am I often angry or without anger? (7) Is my mind often defiled or undefiled? (8) Is my body often agitated or unagitated? (9) Am I often lazy or energetic? (10) Am I often unconcentrated or concentrated?’
“If, by such self-examination, a bhikkhu knows: ‘I am often given to longing, given to ill will, overcome by dullness and drowsiness, restless, plagued by doubt, angry, defiled in mind, agitated in body, lazy, and unconcentrated,’ he should put forth extraordinary desire, effort, zeal, enthusiasm, indefatigability, mindfulness, and clear comprehension to abandon those same bad unwholesome qualities. Just as one whose clothes or head had caught fire would put forth extraordinary desire, effort, zeal, enthusiasm, indefatigability, mindfulness, and clear comprehension to extinguish [the fire on] his clothes or head, so too that bhikkhu should put forth extraordinary desire, effort, zeal, enthusiasm, indefatigability, mindfulness, and clear comprehension to abandon those same bad unwholesome qualities. 
“But if, by such self-examination, a bhikkhu knows: ‘I am often without longing, without ill will, free from dullness and drowsiness, calm, free from doubt, without anger, undefiled in mind, unagitated in body, energetic, and concentrated,’ he should base himself on those same wholesome qualities and make a further effort to reach the destruction of the taints.”
This selection from The Numerical Discourses of the Buddha by Bhikkhu Bodhi is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.
Based on a work at http://www.wisdompubs.org/book/numerical-discourses-buddha.
Permissions beyond the scope of this license may be available at http://www.wisdompubs.org/terms-use.