“When Allah Almighty tried them and they proved steadfast, relinquishing their own personal desires, and when Allah Most High knew that they were not waiting for any reward in this world, now were they desirous to see the victory of this message and the establishment of this Religion on earth by their hands, when their hearts became free of pride of lineage, of nationality, of country, of tribe, of household – in short, when Allah Most High saw them to be morally pure – then He granted them the great trust, the conscious assumption of being Allah’s representative on earth. Since they were pure in faith, the requirement for which is that Allah’s sovereignty alone extend over hearts and consciences in human relationships and morals, in lives and possessions, in modes and manners, Allah Most High knew that they would be true guardians of the political authority, which would be entrusted to them so that they would establish the Divine law and the Divine justice. He knew they would not use it to benefit their own selves or their families or tribe or nation, but would dedicate this authority purely to the service of Allah’s religion and laws, as they knew that the true source of authority is Allah alone and that they were only trustees.”
[Sayyid Qutb (R) in the chapter, “The Nature of the Quranic Method” of his book , Milestones, pp. 44].