Musnad Ahmad 366:1

Ibn Abi ‘Adi narrated to us, from Muhammad ibn Ishaq, from Sulayman ibn Suhaym, from his mother, the daughter of Abu al-Hakam al-Ghifari, who said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "Indeed, a man draws near to Paradise until there is no more than the length of a cubit between him and it, then he speaks a word, and because of it, he moves further away from it than the distance to San‘a."