The Simile of the Mountains
Pabbatopama Sutta  (SN 3:25)

Near Sāvatthī. Then King Pasenadi Kosala went to the Blessed One in the middle of the day and, on arrival, having bowed down to him, sat to one side. As he was sitting there, the Blessed One said to him: “Well now, great king, where are you coming from in the middle of the day?”

“Just now, lord, I was engaged in the sort of royal affairs typical of head-anointed noble-warrior kings intoxicated with the intoxication of sovereignty, obsessed by greed for sensuality, who have attained stable control in their country, and who rule having conquered a great sphere of territory on earth.”

“What do you think, great king? Suppose a trustworthy, reliable man were to come to you from the east. On arrival he would say to you, ‘May it please your majesty to know, I have come from the east. There I saw a great mountain, as high as the clouds, coming this way, crushing all living beings (in its path). Do whatever you think should be done.’ Then a second man were to come to you from the west… Then a third man were to come to you from the north… Then a fourth trustworthy, reliable man were to come to you from the south. On arrival he would say to you, ‘May it please your majesty to know that I have come from the south. There I saw a great mountain, as high as the clouds, coming this way, crushing all living beings. Do whatever you think should be done.’ If, your majesty, such a great peril should arise, such a terrible destruction of human life—the human state being so hard to obtain—what should be done?”

“If, lord, such a great peril should arise, such a terrible destruction of human life—the human state being so hard to obtain—what else should be done but Dhamma-conduct, right conduct, skillful deeds, meritorious deeds?”

“I inform you, great king, I announce to you, great king: aging & death are rolling in on you. When aging & death are rolling in on you, what should be done?”

“As aging & death are rolling in on me, lord, what else should be done but Dhamma-conduct, right conduct, skillful deeds, meritorious deeds?

“There are, lord, elephant battles (fought by) head-anointed noble-warrior kings intoxicated with the intoxication of sovereignty, obsessed by greed for sensuality, who have attained stable control in their country, and who rule having conquered a great sphere of territory on earth; but there is no use for those elephant battles, no scope for them, when aging & death are rolling in. There are cavalry battles… chariot battles… infantry battles… but there is no use for those infantry battles, no scope for them, when aging & death are rolling in. In this royal court there are counselors who, when the enemies arrive, are capable of dividing them by their wits; but there is no use for those battles of wits, no scope for them, when aging & death are rolling in. In this royal court there is abundant bullion & gold stored in vaults & depositories, and with such wealth we are capable of buying off enemies when they come; but there is no use for those battles of wealth, no scope for them, when aging & death are rolling in. As aging & death are rolling in on me, lord, what else should be done but Dhamma-conduct, right conduct, skillful deeds, meritorious deeds?”

“So it is, great king! So it is, great king! As aging & death are rolling in on you, what else should be done but Dhamma-conduct, right conduct, skillful deeds, meritorious deeds?”

That is what the Blessed One said. Having said that, the One Well-Gone, the Teacher, further said this:

See also: MN 82; SN 3:5; AN 6:19–20; Khp 8