Musannaf Ibn Abi Shayba 36:193

Ibn Fudayl narrated to us, from Husayn, from Sa'd ibn Abi 'Ubaydah, from Abu 'Abd al-Rahman, who said: I heard 'Ali saying: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Is he not from the people of Badr? And what makes you know? Perhaps Allah looked upon the people of Badr and said: 'Do what you wish, for Paradise has been made mandatory for you.'"