Mustadrak al-Hakim — Hadith 8599

It is narrated from Hayyah bint Abi Hayyah that she said: A man came to me at midday. I asked: O servant of Allah! What do you need? He said: My companion and I set out in search of our lost camels, and I have come here to rest in the shade and to drink something. So I got up and offered him some sour buttermilk and a little sour milk. Then, looking at him closely, I asked: O servant of Allah! Who are you? He said: I am Abu Bakr, that companion of the Messenger of Allah (peace and blessings be upon him) of whom you have heard. (Hayyah says:) Then I mentioned the tribe of Khath'am and our fighting one another in the Jahiliyyah, and the affection and love that Allah Almighty granted (through Islam), and, mentioning the ropes of the tents, interlaced the fingers together to show it. She says: I asked: O servant of Allah! How long will this state of the people (peace and affection) remain like this? He said: "As long as your leaders (imams) remain upright." I asked: What is meant by the imams? He said: "Have you not seen the tents of a tribe, that they have a chief whom the people follow and obey? So as long as those chiefs remain upright (this matter too will remain upright)."
This hadith is sahih (authentic), but the two Shaykhs (Bukhari and Muslim) did not record it.