The definitive statement regarding the Mahdi issue.

 (The guide is the most knowledgeable of the eye that sees.) 126  Al-Bukhari narrated from Arqiyah Al-Dari that the Prophet (peace be upon him) said: (The greatest of people in my sight is the most fearful of God, and the most complete in his religion, and the most eager to satisfy him.) 127  (Indeed, God's judgment is true and His command is executed.) 128 So, what is the ruling of God if He comes out? Then what is the ruling of the people?

And after this! We rely on authentic hadiths, whose chains of narration are as clear as the sun, regarding the issue of the Mahdi and we debate and argue with them. As for the other issues branching from the original issue, we have used them as evidence, as you see here.

 The establishment of the Imam and his mother is the establishment of the Caliphate.

Imam Al-Shafi'i - may God have mercy on him - said: When the Abbasid Caliphate was established, it was not established by the sword. Rather, it was established by the decree of the Abbasid Caliphate, and the owner of the call for the Abbasid state was Ibrahim bin Mu'awiyah. So Ibrahim bin Mu'awiyah said to him: "O Abu Mu'awiyah, I have been appointed to you, for the matter has been entrusted to you, and it is by your decree that the matter is settled according to what you have found in the books." So he said: "I have been appointed to the Caliphate by the decree of Al-Rabi' bin Mu'awiyah, then the father of Mu'awiyah." 129 And what Imam Al-Shafi'i mentioned is that he did not mention the name of the first, "Ibrahim," but rather mentioned the name of the second, "Al-Rabi'." With these vast principles, Islam had a Caliphate and the Abbasid state was established. If it were not for these principles, it would have been like the Mahdi, whose state and civilization were not established. And whoever opposes us today, we will laugh at him. And he said: "O brothers, how can the Caliphate be established by decree?"