Sahih Bukhari
Accepting Information Given by a Truthful Person
Volume: 009 / Book Number: 091 / Hadith Number: 362
Narrated 'Umar:
There was a man from the Ansar (who was a friend of mine). If he was not present in the company of Allah's Apostle I used to be present with Allah's Apostle, I would tell him what I used to hear from Allah's Apostle, and when I was absent from Allah's Apostle he used to be present with him, and he would tell me what he used to hear from Allah's Apostle .