Musannaf Ibn Abi Shayba 36:395

Ghundar narrated to us, from Shu'bah, from 'Amr ibn Murrah, from Abu al-Bakhtari, from Abu Sa'id al-Khudri, from the Messenger of Allah (may Allah bless him and grant him peace), that he said when this surah was revealed: "When the help of Allah and the victory comes," the Messenger of Allah (may Allah bless him and grant him peace) recited it until he finished it. And he said: "The people are in one group, and I and my companions are in another group." And he said: "There is no migration after the victory, but there is jihad and intention." Marwan said to him: "You have lied." And Zayd ibn Thabit and Rafi' ibn Khadij were with him, and they were sitting with him on the bed. Abu Sa'id said: "If these two wished, they would have told you, but this one fears that you will remove him from the leadership of his people, and this one fears that you will remove him from the collection of charity." So they remained silent. Marwan raised the whip to strike him. When they saw that, they said: "He has spoken the truth."