On the authority of Usamah ibn Zayd (ra) that he heard the Messenger of Allah (saw) sitting, A man will be brought on the Day of Resurrection and thrown into the Fire. His intestines will be hanging out, spilling onto the ground, and he will go around like a donkey goes around a millstone. The inhabitants of the Fire will gather around him and say: “O so and so! What is your affair? Didn’t you used to order us to do good deeds and forbid us from doing bad deeds?” He will reply, “Yes I used to order you to do good deeds, but I did not do them myself, and I used to forbid you from doing bad deeds, yet I used to do them myself”. (al Bukhari, Engl. trans. vol.4, p.315, no. 489; Muslim and others).
The Messenger (saw) also said in a hadith, “During the night of my ascension, I passed by a group of people. Their lips were being severed with scissors of fire. I said, “O Jibreel (as)! Who are these people?” He said, “They are the preachers from your Ummah that would say other than what they would do”. (Ahmad in his Musnad, 3/120, 231, and 239; Ibn Hibban and others, Sahih at-Targheeb, no.120).
On the authority of ‘Umar ibn al Khattab (ra) who said that the Messenger of Allah (saw)
said, “Islam will dominate so that traders frequent the seas and horses enter into the path of Allah. Then there will appear a people who will recite the Qur’an saying, “Who amongst us had memorised the most Qur’an? Who is the most knowledgeable of us? Which of us has the most understanding?” Then he (saw) asked his companions, “Is there any good in them?” They replied, “Allah and His Messenger (saw) know best”. He(saw) said, “They are from you and from this ummah and they are from the fuel of the fire”. (at-Tabarani, in al-Awsat and al-Bazzar, Sahih at-Targheeb wa at-Tarheeb, no.131).
Also in the hadith, “The Qur’an is either a proof for you or against you”. (Muslim,
Engl. trans. vol.1, p.148, no.432; and others).