as He has said: ﴿قُلْ فَلِلَّهِ الْحُجَّةُ الْبَالِغَةُ ۖ فَلَوْ شَاءَ لَهَدَاكُمْ أَجْمَعِينَ﴾[1]; “Say: ‘The conclusive argument belongs to Allah, so if He had willed, He would guide you all’”; and this is what Allah carries out by appointing a Caliph for Himself on the earth whom He has guided to all things, their measures, and their places in the world so that he can put them all in their places and realize justice on His behalf, and he is called “Mahdi”[2] in view of his enjoyment of this divine guidance; because he has been guided by Allah to all things, their measures, and their places in the world.

[The reason for the non-advent of Mahdi on the earth]

It is hereby understood that the purpose of Allah in appointing Mahdi on the earth is to realize justice on it; because Mahdi is the successor of the Prophets, and Allah has said about them: ﴿لَقَدْ أَرْسَلْنَا رُسُلَنَا بِالْبَيِّنَاتِ وَأَنْزَلْنَا مَعَهُمُ الْكِتَابَ وَالْمِيزَانَ لِيَقُومَ النَّاسُ بِالْقِسْطِ﴾[3]; “Indeed, We sent Our Prophets with clear signs and sent down with them the Book and the Balance so that people rise for justice,” and it is clear that the realization of justice on the earth is possible with the advent of Mahdi on it, and therefore, the non-advent of Mahdi on it is not attributed to Allah; because it contradicts His purpose, and contradiction in His purposes is impossible; as He has said: ﴿مَا يُبَدَّلُ الْقَوْلُ لَدَيَّ وَمَا أَنَا بِظَلَّامٍ لِلْعَبِيدِ﴾[4]; “With Me, the Word is not changed, and I do not wrong My servants.” Moreover, the non-advent of Mahdi on the earth obstructs the realization of justice on it, while creating an impediment to the realization of justice on it is oppression, and oppression is not attributed to Allah. As an explanation, the non-advent of Mahdi on the earth is not due to the lack of a reason for his advent; because the reason for his advent is the necessity of the realization of justice on the earth and its being contingent on his advent, which exists, and based on this, his non-advent on the earth is due to the existence of an impediment to his advent, and this impediment, whatever it may be, cannot be the result of Allah’s initial will and action;