Musannaf Ibn Abi Shayba 23:107

'Isa ibn Yunus narrated to us, from al-Awza'i, from Yahya ibn Abi 'Amr al-Shaybani, who said: Hudhayfah said: "I truly know the people of two religions—the people of your religion—who are in the Fire. A people of a religion who say: 'Faith is speech and not action, even if one kills and even if one commits adultery.' And a people of a religion who say: 'If it were, or if he had seen him'—he mentioned a word that escaped me—'you would have commanded us to perform five prayers every day, but they are only two prayers: the prayer of 'Isha and the prayer of Fajr.'"