Narrated AbuSa'id al-Khudri ; Anas ibn Malik:
The Prophet (peace_be_upon_him) said: Soon there will appear disagreement and dissension in my people; there will be people who will be good in speech and bad in work. They recite the Qur'an, but it does not pass their collar-bones. They will swerve from the religion as an animal goes through the animal shot at. They will not return to it till the arrow comes back to its notch. They are worst of the people and animals. Happy is the one who kills them and they kill him. They call to the book of Allah, but they have nothing to do with it. He who fights against them will be nearer to Allah than them (the rest of the people). The people asked: What is their sign? He replied: They shave the head.