Musnad Ahmad

It is narrated from Hazrat Anas (may Allah be pleased with him) that once, during the night, Hazrat Usaid bin Hudair (may Allah be pleased with him) and Abbad bin Bishr (may Allah be pleased with him) were sitting with the Prophet (peace and blessings be upon him) discussing some matter. During this, a large part of the night passed and it was very dark. When they left the Prophet (peace and blessings be upon him) and set out, one of them had a staff in his hand. The staff of one of them became illuminated, and they began to walk in its light. When both of them parted ways, the other's staff also became illuminated.