هُوَ الَّذِي أَرْسَلَ رَسُولَهُ بِالْهُدَىٰ وَدِينِ الْحَقِّ لِيُظْهِرَهُ عَلَى الدِّينِ كُلِّهِ وَلَوْ كَرِهَ الْمُشْرِكُونَ

سوره توبه آیه 33

He it is Who hath sent His messenger with the guidance and the Religion of Truth, that He may cause it to prevail over all religion, however much the idolaters may be averse.

God has promised the total sovereignty of Islam, and His promise is not a lie. As a result, as stated in many narrations, this verse refers to the emergence of Hazrat Mahdi (peace be upon him).