Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
Bukhari :: Book 5 :: Volume 59 :: Hadith 351
Narrated Al-Miswar bin Makhrama:
That 'Amr bin Auf, who was an ally of Bani 'Amir bin Luai and one of those who fought at Badr in the company of the Prophet , said, "Allah's Apostle sent Abu 'Ubaida bin Al-Jarrah to Bahrain to bring the Jizya taxation from its people, for Allah's Apostle had made a peace treaty with the people of Bahrain and appointed Al-'Ala' bin Al-Hadrami as their ruler. So, Abu 'Ubaida arrived with the money from Bahrain. When the Ansar heard of the arrival of Abu 'Ubaida (on the next day) they offered the morning prayer with the Prophet and when the morning prayer had finished, they presented themselves before him. On seeing the Ansar, Allah's Apostle smiled and said, "I think you have heard that Abu 'Ubaida has brought something?" They replied, "Indeed, it is so, O Allah's Apostle!" He said, "Be happy, and hope for what will please you. By Allah, I am not afraid that you will be poor, but I fear that worldly wealth will be bestowed upon you as it was bestowed upon those who lived before you. So you will compete amongst yourselves for it, as they competed for it and it will destroy you as it did them."