Musnad Ahmad 33:1150

Ahmad ibn Abd al-Malik narrated to us, Zuhayr narrated to us, al-A’mash narrated to us, from Abu Sufyan, from Jabir, who said: Abu Shu’ayb had a butcher slave. When he saw the exhaustion that was upon the Messenger of Allah (peace and blessings of Allah be upon him), he ordered his slave to prepare food for him sufficient for five people. He then sent word to the Messenger of Allah (peace and blessings of Allah be upon him) saying, "Come to us as the fifth of five." The Messenger of Allah (peace and blessings of Allah be upon him) stood up, and a man followed him. When he reached his door, he said, "You sent word to me to come to you as the fifth of five, and this man has followed us. If you permit him, he will enter; otherwise, he will return." He said, "I have permitted him, O Messenger of Allah," so he entered.