Translator's note: This discourse mentions the metaphorical notion of "heartwood" (sara) three times. Although sara as a metaphor is often translated as "essence," this misses some of the metaphor's implications. When x is said to have y as its heartwood, that means that the proper development of x yields y, and that y is the most valuable part of x — just as a tree, as it matures, develops heartwood, and the heartwood is the most valuable part of the tree.
"With what virtue, what behavior, nurturing what actions, would a person become rightly based and attain the ultimate goal?" "One should be respectful of one's superiors1 & not envious; should have a sense of the time for seeing teachers2; should value the opportunity when a talk on Dhamma's in progress; should listen intently to well-spoken words; should go at the proper time, humbly, casting off stubborness, to one's teacher's presence; should both recollect & follow the Dhamma, its meaning, restraint, & the holy life. Delighting in Dhamma, savoring Dhamma, established in Dhamma, with a sense of how to investigate Dhamma, one should not speak in ways destructive of Dhamma,3 should guide oneself with true, well-spoken words. Shedding laughter, chattering, lamentation, hatred, deception, deviousness, greed, pride, confrontation, roughness, astringency, infatuation, one should go about free of intoxication, steadfast within. Understanding's the heartwood of well-spoken words; concentration, the heartwood of learning & understanding. When a person is hasty & heedless his discernment & learning don't grow. While those who delight in the doctrines taught by the noble ones, are unexcelled in word, action, & mind. They, established in calm, composure, & concentration, have reached what discernment & learning have as their heartwood."4
Notes
1. According to the Commentary, one's superiors include those who have more wisdom than oneself, more skill in concentration and other aspects of the path than oneself, and those senior to oneself.
2. The Commentary says that the right time to see a teacher is when one is overcome with passion, aversion, and delusion, and cannot find a way out on one's own. This echoes a passage in AN 6.26, in which Ven. Maha Kaccana says that the right time to visit a "monk worthy of esteem" is when one needs help in overcoming any of the five hindrances or when one doesn't yet have an appropriate theme to focus on to put an end to the mind's fermentations.
3. The Commentary equates "words destructive of the Dhamma" with "animal talk." See the discussion under Pacittiya 85 in The Buddhist Monastic Code.
4. The heartwood of learning & discernment is release.