Musnad Ahmad 25:828

Yunus narrated to us, Hammad—meaning Ibn Zayd—narrated to us, from ‘Amr ibn Dinar, from Tawus, from Ibn ‘Abbas: That a Bedouin gave a gift to the Prophet, may Allah bless him and grant him peace, and he rewarded him for it. He said, "Are you satisfied?" He said, "No." So he increased it for him and said, "Are you satisfied?" He said, "No." So he increased it for him and said, "Are you satisfied?" He said, "Yes." The Messenger of Allah, may Allah bless him and grant him peace, then said, "I had intended not to accept a gift except from a Qurayshi, an Ansari, or a Thaqafi."