Thus have I heard. On one occasion the Blessed One was dwelling at Vesali in the Great Wood in the Hall with the Peaked Roof. Now on that occasion the Venerable Visakha Pañcaliputta was instructing, exhorting, inspiring, and gladdening the bhikkhus in the assembly hall with a Dhamma talk, spoken with speech that was polished, clear, articulate, expressing well the meaning, comprehensive, unattached.
Then, in the evening, the Blessed One emerged from seclusion and approached the assembly hall. He sat down in the appointed seat and addressed the bhikkhus thus: “Bhikkhus, who has been instructing, exhorting, inspiring, and gladdening the bhikkhus in the assembly hall with a Dhamma talk, spoken with speech that is polished, clear, articulate, expressing well the meaning, comprehensive, unattached?”
“It was this Venerable Visakha Pañcaliputta, venerable sir.”
Then the Blessed One addressed the Venerable Visakha Pañcaliputta thus: “Good, good, Visakha! It is good that you thus instruct the bhikkhus with a Dhamma talk.”
This is what the Blessed One said … who further said this:
“When the wise man is in the midst of fools
They do not know him if he does not speak,
But they know him when he speaks,
Pointing out the deathless state.“He should speak and explain the Dhamma,
He should raise high the seers’ banner.
Well-spoken words are the seers’ banner:
For the Dhamma is the banner of seers.” sn.ii.281