This book is based on a hadith which is reported by Imam Bukhari in his Sahih al Bukhari and generally known as hadith-e-Jibraeel. In it an angel comes to the prophet and asks him several questions like Iman, Islam, ihsan and the Hour. The Prophet answers all the questions except the last one. When the angel has left the Prophet has said to his companions. ?That was Jibraeel (Gabriel) who came to teach the people their religion.?