Musannaf Ibn Abi Shayba 23:70

Waki’ narrated to us, from al-A’mash, from Abu Wa’il, who said: A man came and said: "I met a group of riders, so I said: 'Who are you?'" He said: "They replied: 'We are the believers.'" He said: "Did you not say: 'We are in Paradise?'"