Musnad Ahmad 1301:9

Hasan narrated to us, he said: Ibn Lahi'ah narrated to us, from Wahb ibn Abdullah, that Abu al-Darda' said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "Whoever says: 'There is no god but Allah, alone, with no partner,' enters Paradise." I said: "Even if he commits adultery and even if he steals?" He said: "Even if he commits adultery and even if he steals." I said: "Even if he commits adultery and even if he steals?" He said: "Even if he commits adultery and even if he steals." I said: "Even if he commits adultery and even if he steals?" He said: "Even if he commits adultery and even if he steals, despite the nose of Abu al-Darda'." He said: So I went out to proclaim it to the people. He said: Then Umar met me and said: "Return, for if the people know of this, they will rely upon it." So I returned and informed the Messenger of Allah, peace and blessings of Allah be upon him, and he, peace and blessings of Allah be upon him, said: "Umar spoke the truth."