Abu Dawud
Battles
Book Number: 032 / Hadith Number: 4305
Narated By Imran ibn Husayn : The Prophet (pbuh) said: Let him who hears of the Dajjal (Antichrist) go far from him for I swear by Allah that a man will come to him thinking he is a believer and follow him because of confused ideas roused in him by him.