Sahih Muslim
The Book Pertaining to Paradise, Its Description, Its Bounties and Its Intimates (Kitab Al-Jannat wa Sifat Naimiha wa Ahliha)
Book Number: 040 / Hadith Number: 6836
Abu Huraira reported Allah's Messenger (may peace be upon him) as say- ing: Many a people with dishevelled hair are driven away from the door (but they are so pious) that if they are to swear in the name of Allah, He would definitely fulfil that.