Sahih Bukhari Volume 005, Book 059, Hadith Number 549.

Narrated By Abu Said Al-Khudri and Abu Huraira : Allah's Apostle appointed a man as the ruler of Khaibar who later brought some Janib (i.e. dates of good quality) to the Prophet. On that, Allah's Apostle said (to him). "Are all the dates of Khaibar like this?" He said, "No, by Allah, O Allah's Apostle! But we take one Sa of these (dates of good quality) for two or three Sa's of other dates (of inferior quality)." On that, Allah's Apostle said, "Do not do so, but first sell the inferior quality dates for money and then with that money, buy Janib." Abu Said and Abu Huraira said, "The Prophet made the brother of Bani Adi from the Ansar as the ruler of Khaibar.

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