At Aruṇavatī
Aruṇavatī Sutta  (SN 6:14)

On one occasion the Blessed One was dwelling in Sāvatthī. There he addressed the monks, “Monks!”

“Yes, lord,” the monks responded to the Blessed One.

The Blessed One said, “In the past, monks, was a king named Aruṇavant whose royal city was named Aruṇavatī. And in dependence on that royal city of Aruṇavatī there dwelled Sikhī the Blessed One, worthy & fully self-awakened. And Sikhī the Blessed One, worthy & fully self-awakened, had a pair of disciples named Abhibhū & Sambhava as his foremost pair, his excellent pair.

“Then Sikhī the Blessed One, worthy & fully self-awakened, addressed the monk Abhibhū: ‘Come, brahman, let’s go to a certain Brahmā world until the time for the meal.’

“‘As you say, lord,’ the monk Abhibhū responded to Sikhī the Blessed One, worthy & fully self-awakened.

“Then—just as a strong man might extend his flexed arm or flex his extended arm—Sikhī the Blessed One, worthy & fully self-awakened, & the monk Abhibhū disappeared from the royal city of Aruṇavatī and reappeared in that Brahmā world.

“Then Sikhī the Blessed One, worthy & fully self-awakened, addressed the monk Abhibhū: ‘Let a Dhamma talk come to you, brahman, for Brahmā, Brahmā’s retinue, & Brahmā’s assembly.’

“Responding, ‘As you say, lord,’ to Sikhī the Blessed One, worthy & fully self-awakened, the monk Abhibhū instructed, urged, roused, & encouraged Brahmā, Brahmā’s retinue, & Brahmā’s assembly with a Dhamma talk.

“With that, Brahmā, Brahmā’s retinue, & Brahmā’s assembly were indignant, annoyed, & complained: ‘Isn’t it amazing, good sirs! Isn’t it astounding! How can this disciple, in the presence of his teacher, teach the Dhamma?’

“Then Sikhī the Blessed One, worthy & fully self-awakened, addressed the monk Abhibhū: ‘Brahmā, Brahmā’s retinue, & Brahmā’s assembly are indignant & annoyed with you. They complain: “Isn’t it amazing, good sirs! Isn’t it astounding! How can this disciple, in the presence of his teacher, teach the Dhamma?” Very well then, strike terror in Brahmā, Brahmā’s retinue, & Brahmā’s assembly to an even greater degree.’

“Responding, ‘As you say, lord,’ to Sikhī the Blessed One, worthy & fully self-awakened, the monk Abhibhū taught the Dhamma with his body visible, taught the Dhamma with his body invisible, taught the Dhamma with the lower half of his body visible & the upper half invisible, taught the Dhamma with the upper half of his body visible & the lower half invisible.

“With that, the minds of Brahmā, Brahmā’s retinue, & Brahmā’s assembly were overcome with amazement & astonishment: ‘Isn’t it amazing, good sirs! Isn’t it astounding!—the contemplative’s great power & great might!’

“Then the monk Abhibhū said to Sikhī the Blessed One, worthy & fully self-awakened, ‘I recall, lord, having made this statement while standing in the midst of the Saṅgha of monks: “I can, friends, while standing in the Brahmā world, make my voice heard throughout the thousand-fold cosmos.”’

“‘This is the time, brahman! This is the time, brahman, for you, while standing in the Brahmā world, to make your voice heard throughout the thousand-fold cosmos!’

“Responding, ‘As you say, lord,’ to Sikhī the Blessed One, worthy & fully self-awakened, the monk Abhibhū, while standing in the Brahmā world, recited these verses:

‘Rouse yourselves.
	Go forth.
Commit yourselves
to the Awakened One’s bidding.
Scatter the army of Death
as an elephant would
a shed made of reeds.
He who,
in this Dhamma & Vinaya,
stays heedful,
abandoning birth,
	the wandering-on,
will put an end
to suffering & stress.’

“Then—having struck terror in Brahmā, Brahmā’s retinue, & Brahmā’s assembly—Sikhī the Blessed One, worthy & fully self-awakened, & the monk Abhibhū—just as a strong man might extend his flexed arm or flex his extended arm—disappeared from that Brahmā world and reappeared in the royal city of Aruṇavatī.

“Then, monks, Sikhī the Blessed One, worthy & fully self-awakened, addressed the monks, ‘Monks, did you hear the monk Abhibhū reciting verses while standing in the Brahmā world?’

“‘Lord, we heard the monk Abhibhū reciting verses while standing in the Brahmā world.’

“‘But what verses did you hear the monk Abhibhū reciting while standing in the Brahmā world?’

“‘Lord, we heard the monk Abhibhū reciting these verses while standing in the Brahmā world:

“Rouse yourselves.
	Go forth.
Commit yourselves
to the Awakened One’s bidding.
Scatter the army of Death
as an elephant would
a shed made of reeds.
He who,
in this Dhamma & Vinaya,
stays heedful,
abandoning birth,
	the wandering-on,
will put an end
to suffering & stress.”

“‘These, lord, are the verses we heard the monk Abhibhū reciting while standing in the Brahmā world.’

“‘Good, monks. It’s good that you heard the monk Abhibhū reciting verses while standing in the Brahmā world.’”

That is what the Blessed One said. Gratified, the monks delighted in the Blessed One’s words.

See also: MN 49; Thag 3:13