The debate between Imam Reda (as) and scholars about the difference between "the itra" and the "nation".
I will translate the hadith (or alter some translation online because it's not fully accurate), then comment on it:
Imam Ar-Reza (peace be upon him) was attendant in a session that included the best scholars of Iraq and Khurasan when Al-Ma'mun asked them about the exegesis of God's saying: "Then we gave the book as an inheritance to those we chosen from among our servants so among them is who is oppressive to their souls, and so among is who is a middle course, and among them is who races ahead in good deeds by permission of God. This is indeed a great favor. They answered that the Verse refers to all the umma.
Al-Ma'mun then turned to Imam Ar-Reza (peace be upon him) and asked for his opinion. The Imam answered: I do not agree with them. I say that God the Blessed refers to the immaculate family of the Prophet (peace be upon him and his family) exclusively. Al-Ma'mun asked for an explanation. The Imam (peace be upon him) explained: If God referred to the umma, they all should be in Paradise. This is for His saying: …among them is who is oppressive to their souls, and so among is who is a middle course, and among them is who races ahead in good deeds by permission of God. This is indeed a great favor.
God then informs that all of them will be in Paradise. He the Majestic said:
They will enter the gardens of Eden… Thus, the Verse refers to the immaculate progeny of the Prophet (peace be upon him and his family) exclusively. Imam Ar-Reza (peace be upon him) then added: The immaculate progeny are those whom God describes in His Book by saying: People of the house, God wants to remove all kinds of uncleanness from you and to purify you thoroughly. The Prophet (peace be upon him and his family) said about them: "I am leaving among you the two weighty things- the Book of God and my progeny; my family. They will not depart each other until they will join me on the Divine Pool. Consider how will you regard me in treating them. O people, do not suggest to them, because they are more knowledgeable than you. The scholars asked Abul-Hasan (peace be upon him) whether the itra of the Prophet and the Prophet's aul are the same. The Imam (peace be upon him) answered that they are the same. The scholars claimed that the Prophet (peace be upon him and his family) is related to have said, "My umma is my family," and the Prophet's companions agreed unanimously on the fact that Mohammed's family is his umma. Imam Ar-Reza (peace be upon him) worded:
Well, tell me whether it is lawful for Mohammed's family to have any alms in possession. "No, it is unlawful," answered the scholars. Then the Imam (peace be upon him) asked: Tell me whether it is lawful for the umma to have the alms in possession. "Yes, it is lawful for them," answered they. The Imam (peace be upon him) commented: This is one difference between Mohammed's family and the umma. Woe to you! Where are you misled? Do you ignore the Quran or are you transgressing people? Have you not known that this narrative is obviously dedicated to the guided choice ones exclusively? "How can you prove this, Abul-Hasan?" asked the scholars. The Imam (peace be upon him) answered:
This is clear in God's saying:
We sent Noah and Abraham and placed prophethood and the Book among their offsprings, some of whom have the right guidance. However, most of them are evildoers. Hence, the inheritance of the Book is dedicated to the guided ones, not the evildoers. In his supplication to his Lord, Noah said -as God relates in the Quran-: Lord, my son is a member of my family. Your promise is always true and you are the best Judge. He said so after God had promised to save his family and him. However, God the Exalted answered him: He is not one of your family. He is a man of unrighteous deeds. Do not ask me about that which you have no knowledge. I advise you not to become an ignorant person.
Al-Ma'mun asked: "Did God give distinction to the Prophet's family over people?" The Imam (peace be upon him) answered: God the Majestic the Omnipotent gave distinction of the Prophet's family over people in the Wise Book. Al-Ma'mun asked for examples, and the Imam (peace be upon him) cited: God says: God chose (and gave distinction to) Adam, Noah, the family of Abraham, and Imran over all the people of the world. They were the offspring of one another. In another place in the Quran, God says:
Are they jealous of God's grave over the humans? For We have given to the family of Abraham the Book, Wisdom, and a great Authority.(4:54) Then God refers this to the believers at whom he addressed: Believers, obey God and Obey His Messenger, and Those who hold the Authority from you. In the previous Verse, God refers to the qualified leaders to whom He gave the Book and wisdom in inheritance, but people envied them for these two things as He affirms in His saying: "Are they jealous of the favors that God has done to some people? We have given to the family of Abraham the Book, Wisdom, and a great Authority." The grace stand for the (obligatory) obedience to the immaculate choice ones and the great authority stands for the obedience to them.
"Does God the Elevated explains this selection in the Book?" asked the scholars. The Imam (peace be upon him) answered: God explains this selection obviously in twelve Verses in the Book and refers to it in many Verses whose meanings are hidden. First, it is explained in God's saying: And warn your nearest relations. Ubay bin Ka'b adds 'and your selected family,' to the previous Verse, and the addition is recorded in Abdullah bin Mas'ud's copy of the Holy Quran. When Othman (bin Affan) ordered Zaid bin Thabit to compile the Quran, he bypassed that statement, which is certainly a sublime standing, a great excellence, and a grand honor for the Prophet's family whom are exclusively stated in the previous Verse. [I will explain why Imam Reda (as) said this, it doesn't mean there is anything missing in Quran - it's referring to the war against the Sunnah and commentary from Companions by the first 3 Caliphs, will go into detail in this later]
The second Verse of the selection is God's saying: "God only desires to keep/remove the uncleanness away from you O people of the House and purify you a purification" Except the obstinate, no one can deny this merit because it is obviously clear. The third Verse of selection is that in which God gave distinction to the Immaculates over all others and ordered His Prophet in His saying: If anyone disputes (your prophesy) after knowledge has come to you, say, "Let each of us bring our children, women, and ourselves to one place and pray to God to condemn the liars among us."
The Prophet (peace be upon him and his family) carried out this order when he brought Ali, Al-Hasan, Al-Hussein, and Fatima (peace be upon them) for praying to God for condemning the lying party. Thus, God added them to the Prophet. Do you know the indication of God's saying: "…and ourselves…?" The scholars said: "This is the Prophet's personality."
Imam Ar-Reza (peace be upon him) commented: This is not accurate. It is an indication to Ali (peace be upon him). This can be proved by the Prophet's saying: "Let the Luhai'as keep on doing so and I will subjugate them to a man who is like myself-Ali." No one can precede this particularity, disagree about this virtue, or overtake this honor. Thus, the Prophet (peace be upon him and his family) compared Ali's personality to his. The fourth Verse of selection is that when the Prophet ordered everybody to leave the Mosque except his family. People showed dissatisfaction for such a procedure and Al-Abbas discussed the Prophet (peace be upon him and his family) in the question, but the Prophet answered: "It was not I who dismissed you all except Ali. It was God who did so." This is a clear explanation of the Prophet's saying to Ali: "Your relation to me is as same as Aaron's to Moses."
"What is the relation between this and the Quran?" asked the scholars. Imam Ar-Reza (peace be upon him) answered: This is in the Quran in God's saying: We sent a revelation to Moses and his brother to build houses for their people in the Pharaoh's town and to build them facing one another. This Verse shows Aaron's relation to Moses. It also shows Ali's standing to the Prophet (peace be upon him and his family). Besides, there is a clear evidence in the Prophet's saying: "Except Mohammed and Mohammed's family, all the ceremonially impure and the menstruant are forbidden from entering this Mosque."
"This explanation and evidence cannot be found with anyone other than you, the Prophet's family," said the scholars. Imam Ar-Reza (peace be upon him) commented:
Who can deny this fact? The Prophet (peace be upon him and his family) said: "I am the city of knowledge, and Ali is its portal. He whoever betakes himself to the city of knowledge should first see its portal." The previous clear explanation of the virtue, honor, preference, selection, and immaculacy cannot be denied by anyone except the obstinate. All praise belongs to God for so. The fifth Verse of selection is God's saying:
Give the relatives their dues. Almighty God gave this particularity to the Prophet's family exclusively as a sign of their distinction over the umma. When this Verse was revealed to the Prophet (peace be upon him and his family), he summoned Fatima, his daughter, and said to her, "Fadak is one of the territories that we did not exhaust our horses or camels to seize them; therefore, it is mine exclusively . Now, I gift it to you and your offspring according to God's instructions."