At one time, the Venerable Mahākaccāna was dwelling in Madhurā, in Gunda's Grove.
Then, the brahmin Kandarāyana approached the Venerable Mahākaccāna and, after exchanging greetings, sat down to one side. Seated there, the brahmin Kandarāyana said to the Venerable Mahākaccāna:
"I have heard it said, good Kaccāna, that 'Kaccāna the recluse does not show respect to aged, elderly, senior, long-standing brahmins by rising up, offering a seat, or greeting them.' Is this true, good Kaccāna? Is it correct that you, Kaccāna, do not show respect to aged, elderly, senior, long-standing brahmins by rising up, offering a seat, or greeting them? This is not proper, good Kaccāna."
"There is, brahmin, a distinction explained by the Blessed One, who knows and sees, the Arahant, the Perfectly Enlightened One, between the status of the elder and the status of the youth. A person may be old, eighty, ninety, or a hundred years of age by birth, but if he indulges in sensual pleasures, lives amidst sensual pleasures, burns with the fever of sensual pleasures, is consumed by sensual thoughts, and is agitated by the search for sensual pleasures, then such a person, though old, is considered immature, not an elder. Conversely, a person may be young, a youth with black hair, blessed with youth and the prime of life. But if he does not indulge in sensual pleasures, does not live amidst sensual pleasures, is not burned by the fever of sensual pleasures, is not consumed by sensual thoughts, and is not agitated by the search for sensual pleasures, then such a person, though young, is considered wise, and is indeed an elder."
Having said this, the brahmin Kandarāyana rose from his seat, arranged his upper robe over one shoulder, and bowed his head at the feet of the hundred young bhikkhus, saying: "You are elders, standing on the ground of elders. We are youths, standing on the ground of youths."
"Excellent, good Kaccāna! ... From this day forth, let the Venerable Kaccāna consider me as a lay follower who has gone for refuge for life."
Related Teachings:
Characteristics of an immature person and a wise person (AN 3.2) - A wise person should be recognized by three qualities. What are these three? Bodily good conduct, verbal good conduct, and mental good conduct.
Independently verifying and understanding the unwholesome qualities and the wholesome qualities (AN 3.66) - This is a teaching in line with the overall teachings of the Buddha where he recommends against creating beliefs and assumptions (perceptions) based on how things seem.