The Quran itself is the proof of Muhammad being the Prophet of God. The Quran calls mankind towards the right path, i.e. the path of righteousness. None of its contents clash with reason and nature. Even fifteen hundred years after the Quran was first revealed, nothing has been detected in it which can be called as irrational or unnatural. This distinct characteristic of the Quran is the greatest proof of its being the book of God. ‘So that you may warn a people.’ Here, ‘people’ refers to the Children of Isma‘il. Every prophet is raised primarily to address his contemporaries. Accordingly, the first addressees of the Prophet Muhammad were his own tribesmen. But although the institution of prophethood ended with him, the Prophethood of Muhammad shall continue until Doomsday—the difference being that, with the Children of Isma‘il, he personally and directly fulfilled his mission, while in respect of all other nations after him, the task of giving the call and fulfilling the mission shall have to be performed by his followers.