From Sahih Bukhari (Hadith 3639):
Narrated Anas:Once two men from the companions of Allah's Messenger (ﷺ) went out of the house of the Prophet (ﷺ) on a very dark night. They were accompanied by two things that resembled two lamps lighting the way in front of them, and when they parted, each of them was accompanied by one of those two things (lamps) till they reached their homes
Reference: Bukhari 3639