From Sahih Bukhari (Hadith 7254):
Narrated Hudhaifa:The Prophet (ﷺ) said to the people of Najran, "I will send to you an honest person who is really trustworthy." The Companion, of the Prophet (ﷺ) each desired to be that person, but the Prophet (ﷺ) sent Abu 'Ubaida
Reference: Bukhari 7254