Sahih al-Bukhari Book 34, Hadith 75
Once the Prophet (ﷺ) went out during the day. Neither did he talk to me nor I to him till he reached the
market of Bani Qainuqa and then he sat in the compound of Fatima's house and asked about the small
boy (his grandson Al-Hasan) but Fatima kept the boy in for a while. I thought she was either changing
his clothes or giving the boy a bath. After a while the boy came out running and the Prophet (ﷺ) embraced
and kissed him and then said, 'O Allah! Love him, and love whoever loves him.'
A man at Al-Baqi' called, "O Abul-Qasim!" The Prophet (ﷺ) turned to him and the man said (to the Prophet ), "I did not intend to call you." The prophet said, "Name yourselves by my name but not by my Kunya (name).
Ibn `Umar told us that the people used to buy food from the caravans in the lifetime of the Prophet. The Prophet (ﷺ) used to forbid them to sell it at the very place where they had purchased it (but they were to wait) till they carried it to the market where foodstuff was sold. Ibn `Umar said, 'The Prophet (ﷺ) also forbade the reselling of foodstuff by somebody who had bought it unless he had received it with exact full measure.'