Sahih Al Bukhari – Book of Virtues And Merits Of The Prophet (pbuh) And His Companions

Volumn 004, Book 056, Hadith Number 678.
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Narated By Abu Huraira : Allah's Apostle said, "A man bought a piece of and from another man, and the buyer found an earthenware jar filled with gold in the land. The buyer said to the seller. 'Take your gold, as I have bought only the land from you, but I have not bought the gold from you.' The (former) owner of the land said, "I have sold you the land with everything in it.' So both of them took their case before a man who asked, 'Do you have children?' One of them said, "I have a boy.' The other said, "I have a girl.' The man said, 'Marry the girl to the boy and spend the money on both of them and give the rest of it in charity.'"