قال أبو جعفر مصنف هذا الكتاب: الدليل على عصمة الامام أنه لما كان كل كلام ينقل عن قائله يحتمل وجوها من التأويل وكان أكثر القرآن والسنة مما أجمعت الفرق على أنه صحيح لم يغير ولم يبدل ولم يزد فيه ولم ينقص منه محتملا لوجوه كثيرة من التأويل وجب أن يكون مع ذلك مخبر صادق معصوم من تعمد الكذب والغلط، منبئ عما عنى الله ورسوله في الكتاب والسنة على حق ذلك وصدقه، لان الخلق مختلفون في التأويل، كل فرقة تميل مع القرآن والسنة إلى مذهبها، فلو كان الله تبارك وتعالى تركهم بهذه الصفة من غير مخبر عن كتابه صادق فيه لكان قد سوغهم الاختلاف في الدين ودعاهم إليه إذ أنزل كتابا يحتمل التأويل وسن نبيه صلى الله عليه وآله سنة يحتمل التأويل وأمرهم بالعمل بهما، فكأنه قال: تأولوا واعملوا. وفي ذلك إباحة العمل بالمتناقضات والاعتماد للحق وخلافه. فلما استحال ذلك على الله عز وجل وجب أن يكون مع القرآن والسنة في كل عصر من يبين عن المعاني التي عناها الله عز وجل في القرآن بكلامه دون ما يحتمله ألفاظ القرآن من التأويل ويبين عن المعاني التي عناها رسول الله صلى الله عليه وآله في سننه وأخباره دون التأويل الذي يحتمله ألفاظ الاخبار المروية عنه عليه السلام المجمع على صحة نقلها، وإذا وجب أنه لا بد من مخبر صادق وجب أن لا يجوز عليه الكذب تعمدا ولا الغلط فيما يخبر به   عن مراد الله عز وجل في كتابه وعن مراد رسول الله صلى الله عليه وآله في أخباره وسننه، و إذا وجب ذلك وجب أنه معصوم. ومما يؤكد هذا الدليل أنه لا يجوز عند مخالفينا أن يكون الله عز وجل أنزل القرآنعلى أهل عصر النبي صلى عليه وآله ولا نبي فيهم ويتعبدهم بالعمل بما فيه على حقه و صدقه فإذا لم يجز أن ينزل القرآن على قوم ولا ناطق به ولا معبر عنه ولا مفسر لما استعجم منه ولا مبين لوجهه فكذلك لا يجوز أن نتعبد نحن به إلا ومعه من يقوم فينا مقام النبي صلى الله عليه وآله في قومه وأهل عصره في التبيين لناسخه ومنسوخه وخاصه وعامه، و المعاني التي عناها الله عز وجل بكلامه، دون ما يحتمله التأويل، كما كان النبي صلى الله عليه وآله مبينا لذلك كله لأهل عصره ولا بد من ذلك ما لزموا العقول والدين. فإن قال قائل: إن المودي إلينا ما نحتاج إلى علمه من متشابه القرآن ومن معانيه التي عناها الله دون ما يحتمله ألفاظه هو الأمة. أكذبه اختلاف   الأمة وشهادتها بأجمعها على أنفسها في كثير من آي القرآن لجهلهم بمعناه الذي عناه الله عز وجل، وفي ذلك بيان أن الأمة ليست هي المؤدية عن الله عز وجل ببيان القرآن، وأنها ليست تقوم في ذلك مقام النبي صلى الله عليه وآله. فإن تجاسر متجاسر فقال: قد كان يجوز أن ينزل القرآن على أهل عصر النبي صلى الله عليه وآله ولا يكون معه نبي ويتعبدهم بما فيه مع احتماله للتأويل. قيل له: فهب ذلك كان قد وقع   من الخلاف في معانيه ما قد وقع في هذا الوقت ما الذي كانوا يصنعون؟ فإن قال: ما قد صنعوا الساعة. قيل: الذي فعلوه الساعة أخذ كل فرقة من الأمة جانبا من التأويل وعمله عليه وتضليل الفرقة المخالفة لها في ذلك وشهادتها عليها بأنها ليست على الحق. فإن قال: إنه كان يجوز أن يكون أول الاسلام كذلك وإن ذلك حكمة من الله و عدل فيهم. ركب خطأ عظيما وما لا أرى أحدا من الخلق يقدم عليه، فيقال له عند ذلك:فحدثنا إذا تهيأ للعرب الفصحاء أهل اللغة أن يتأولوا القرآن ويعمل كل واحد منهم بما يتأوله على اللغة العربية فكيف يصنع من لا يعرف اللغة من الناس؟ وكيف يصنع العجم من الترك والفرس؟ وإلى أي شئ يرجعون في علم ما فرض الله عليهم في كتابه؟ و من أي الفرق يقبلون مع اختلاف الفرق في التأويل وإباحتك كل فرقة أن تعمل بتأويلها فلا بد لك من أن تجري العجم ومن لا يفهم اللغة مجرى أصحاب اللغة من أن لهم أن يتبعوا أي الفرق شاؤوا. و [إلا] إن ألزمت   من لا يفهم اللغة اتباع بعض الفرق دون بعض لزمك أنت تجعل الحق كله في تلك الفرقة دون غيرها، فإن جعلت الحق في فرقة دون فرقة نقضت ما بنيت عليه كلامك واحتجت إلى أن يكون مع تلك الفرقة علم وحجة تبين بها من غيرها وليس هذا من قولك لو جعلت الفرق كلها متساوية في الحق مع تناقض تأويلاتها فيلزمك أيضا أن تجعل للعجم ومن لا يفهم اللغة أن يتبعوا أي الفرق شاؤوا، وإذا فعلت ذلك لزمك في هذا الوقت أن لا تلزم   أحدا من مخالفيك من الشيعة والخوارج وأصحاب التأويلات وجميع من خالفك ممن له فرقة ومن مبتدع لا فرقة له على مخالفيك ذما  ، وهذا نقض الاسلام والخروج من الاجماع، ويقال لك: وما ينكر على هذا الاعطاء   أن يتعبد الله عز وجل الخلق بما في كتاب مطبق لا يمكن أحدا  أن يقرأ ما فيه ويأمر أن يبحثوا ويرتادوا ويعمل كل فرقة بما ترى أنه في الكتاب. فإن أجزت ذلك أجزت على الله عز وجل العبث لان ذلك صفة العابث، ويلزمك أن تجيز على كل من نظر بعقله في شئ واستحسن أمرا من الدين أن يعتقده لأنه سواء أباحهم أن يعملوا في أصول الحلال و الحرام وفروعها بآرائهم [أ] وأباحهم أن ينظروا بعقولهم في أصول الدين كله وفروعه من توحيده وغيره وأن يعملوا أيضا بما استحسنوه وكان عندهم حقا فإن أجزت ذلك أجزت على الله عز وجل أن يبيح الخلق أن يشهدوا عليه أنه ثاني اثنين، وأن يعتقدوا الدهر، وجحدوا البارئ جل وعز. وهذا آخر ما في هذا الكلام لان من أجاز أن يتعبدنا الله عز وجل بالكتاب على احتمال التأويل ولا مخبر صادق لنا عن معانيه لزمه أن يجيز على أهل عصر النبي صلى الله عليه وآله مثل ذلك وإذا أجاز مثل ذلك لزمه أن يبيح الله عز وجل كل فرقة العمل بما رأت وتأولت لأنه لا يكون لهم غير ذلك إذا لم يكن معهم حجة في أن هذا التأويل أصح من هذا التأويل، وإذا أباح ذلك أباح متبعهم   ممن لا يعرف اللغة وإذا أباح أولئك أيضا لزمه أن يبيحنا في هذا العصر، وإذا أباحنا ذلك في الكتاب لزمه أن يبيحنا ذلك في أصول الحلال والحرام ومقائس العقول وذلك خروج من الدين كله، وإذا وجب بما قدمنا ذكره أنه لا بد من مترجم عن القرآن وأخبار النبي صلى الله عليه وآله وجب أن يكون معصوما ليجب القبول منه، فإذا وجب أن يكون معصوما بطل أن يكون هو الأمة لما بينا من اختلافاتها في تأويل القرآن والاخبار وتنازعها في ذلك ومن إكفار بعضها بعضا، وإذا ثبت ذلك وجب أن المعصوم هو الواحد الذي ذكرناه وهو الامام. وقد دللنا على أن الامام لا يكون إلا معصوما وأرينا أنه إذا وجبت العصمة في الامام لم يكن بد من أن ينص النبي صلى الله عليه وآله عليه لان العصمة ليست في ظاهر الخلقة فيعرفها الخلق بالمشاهدة فواجب أن ينص عليها علام الغيوب تبارك وتعالى على لسان نبيه صلى الله عليه وآله وذلك لان الامام لا يكون إلا منصوصا عليه. وقد صح لنا النص بما بيناه من الحجج وبما رويناه من الأخبار الصحيحة.
Abu Ja’far, the compiler of this book, said: The evidence to the Imam’s Infallibility is that since every speech that is transmitted of a sayer is possible to have indications of interpretations, and since most of the Qur’an and the Tradition is what sects have gathered upon as being authentic, not having changed, nor replaced, nor having been increased with nor having been deducted from, are possible to have many indications of interpretation, it is necessary for there to be, with that, an informer who is truthful, protected from purposeful lying and mistake, predicting of what Allah and His Messenger meant in the Book and Tradition in its true and real sense. This is because the creation are disputed with regards to interpretation; every sect tendences along with the Qur’an and the Tradition towards its own opinions. If Allah, Blessed and Exalted is He, had left them in this case without an informer of His Book who is truthful about it, then He would have justified for them to be disputed in matters of religion, yet He would have called them to it, as He had sent down a Book that is possible to have several interpretations, and as His Prophet, Allah’s blessings be upon him and his Family, established a Tradition that is possible to have several interpretations, and yet He has ordered them to act in accordance to it. It is as if He said: Interpret and act. In that lies permissibility of acting with contradictions and of relying on the truth and its opposite. Since that is impossible upon Allah, Exalted and Glorious is He, it is necessary for there to be along with the Qur’an and the Tradition, in every age, one who clarifies the meanings which Allah, Exalted and Glorious is He, meant in the Qur’an with His speech with other than what the terms of the Qur’an carries of possible interpretation, and who clarifies the meanings which the Messenger of Allah, Allah’s blessings be upon him and his Family, meant in his Traditions and reports with other than the possible interpretation of the terms of the reports narrated of him, peace be upon him, on whose authenticity of transmission there is a consensus. If it is necessary that there must be a truthful informer, it is necessary for it to be impossible for him to purposely lie and err in his informing of the intention of Allah, Exalted and Glorious is He, in His Book and the intention of Allah’s Messenger, Allah’s blessings be upon him and his Family, in his reports and Traditions. Since this is necessary, it is necessary for him to be Infallible. What affirms this evidence is that it is not permissible to our opponents for Allah, Exalted and Glorious is He, to have sent down the Qur’an to the people of the era of the Prophet, Allah’s blessings be upon him and his Family, while there was no Prophet among them and that He would command them to act with it in its true and real sense. Hence, if it is not possible that He had sent down the Qur’an upon a people while there is no speaker on its behalf, no expressor on its behalf, nor interpreter of what is obscure of it nor clarifier of its indications, similarly, it is not possible for us to act with it except if there is, along with it, one who takes among us the position of the Prophet, Allah’s blessings be upon him and his Family, in his people and the people of his era with regards to clarifying its abrogator, abrogated, specific and general elements, and the meanings which Allah, Exalted and Glorious is He, intended with His Speech, with that which does not possibly contain interpretation, like how the Prophet, Allah’s blessings be upon him and his Family, was a clarifier of all of that to the people of his age. That is a must, as long as they adhere to intellect and religion. If a sayer was to say: That which delivers to us what we need to know of the unclear elements of the Qur’an and of the meanings intended by Allah, with other than that whose terms may not possibly contain of that, is the nation. That which negates this the most is the nation’s dispute and testimony, in consensus, upon itself in many of the verses of the Qur’an to their ignorance of its meaning which Allah, Exalted and Glorious is He, intended. In that lies clarification that the nation is not the deliverer on behalf of Allah, Exalted and Glorious is He, which clarifies the Qur’an, and that in that it does not take the position of the Prophet, Allah’s blessings be upon him and his Family. If a daring was to dares and say: Certainly, it would be possible for Him to have sent down the Qur’an on the people of the era of the Prophet, Allah’s blessings be upon him and his Family, while there is no Prophet with them, and that He would command them to act in worship with what is in it, in spite that interpretation is possible in it. It would be said to him: Suppose that this had caused of dispute in its meanings what has occurred in this age, what would they do? If he would say: What they do at this hour. It would be said: What they have done at this hour is for every sect of the nation to take one side of the interpretation and act with it while declaring as aberrant the sect that opposes them in it and testifying against it that it is not on the truth. If he was to say: It is possible for there to have been so during the first stages of Islam, and in that lies wisdom from Allah and justice towards them. He would (in the case of this statement) have performed a major error and which I have not seen any of the creation daring to, and it would be said to him after that: Then tell us, if it was feasible for the fluent Arabs, the people of the language, to interpret the Qur’an and for each one of them to act with what he interprets of the Arabic language, then what will they do, those of the people who do not know the language? And how will they non-Arabs, of the Turks and the Persians, do? And to what thing will they refer back with regards to knowledge of what Allah has obliged upon them in His Book? And from which sect will they accept, with the dispute among sects with regards to interpretation and your declaration of the permissibility for each sect to act in accordance with its interpretation? Hence, it would be a must for you make the non-Arabs and those who do not understand the language follow the path of the people of the language in the sense that they may follow whichever of the sects they wish. Otherwise, if you would bind upon those who do not understand the language to follow some sects and not others, it implies that you place all the truth with that sect and not others. Hence, if you place the truth in, you would have negated what you based your speech upon, and you would need for there to be with that sect a knowledge and proof by that recognize it (as the truth) from others, and that is not of your saying in which you make all sects equal with regards to the truth in spite of the contradiction between their interpretations. It would then be necessary for you to make for the non-Arabs and those who do not understand the language that they follow whichever of the sects they wish. If you do so, it would imply, at this time, that you do not bind upon any of your opponents, from the Shi’a, Khawarij, people of interpretations and everyone who opposes you from those who have a sect and from innovators who do not have a sect, a condemnation. This is a negation of Islam and violation of the consensus, and it will be said to you: Is it not a condemned opinion that Allah commands the creation to act in worship with the content in a Book that is agreed upon, which none is able to read its content, and that He commands them to research and explore, and that each sect acts with what it sees is in the Book? If you had declared this as permissible, you would have declared frivolity as permissible for Allah, Exalted and Glorious is He, because that is, indeed, among the characteristics of a frivolous. Also, it implies that you declare as permissible for everyone who ponders upon a thing with his intellect and considers something of religion as good, that he believes in it, because it would be equal; He would have permitted them to act with the foundations of what is allowable and forbidden and its branches by their opinions, or he would permit for them to ponder with their intellects into the roots of religion, all of it, and its branches, from its (tenet of) Monotheism and others, and that they also act with what they consider as good and rely on to be true. If you declare that as permissible, you would have declared it possible for Allah, Exalted and Glorious is He, to allow for the creation that they testify for Him that He is the second of two, to believe in existentialism and to knowingly reject the Creator, Glorious and Exalted is He. This is the last there is of this speech, because the one who declares as possible that Allah, Exalted and Glorious is He, commands us to act in worship by the Book whilst there being the possibility of interpretation and there not being an informer who is truthful to us about its meanings, implies that he declares as permissible for the people of the era of the Prophet, Allah’s blessings be upon him and his Family, the same as that, and if he declares the same as that as permissible, it implies that Allah, Exalted and Glorious is He, allows for every sect to act in accordance to what it believes and interprets, because they would not have other than that if they were not to have any proof with regards to this interpretation being more correct than that interpretation. If He has allowed that for them, (it implies that) He has allowed for their follower who does not know the knowledge, and if He allows for those as well, it implies that He allows for us in this age. If He allows that for us with regards to the Book, it implies that He allows that for us with regards to the foundations of what is allowable and forbidden and analogies of the intellect, and that is an exiting of the Religion, all of it. If it is necessary with what we have previously mentioned with regards to that there must be an interpreter on behalf of the Qur’an and the reports of the Prophet, Allah’s blessings be upon him and his Family, it is necessary that he is Infallible, in order for it to be obligatory to accept from him, and if it is necessary that he is Infallible, it is invalidated that this applies to the nation due to what we have clarified of its dispute in the interpretation of the Qur’an and the reports, its quarreling with regards to that and its declaration of each other to be disbelievers. If that is affirmed, it is necessary for the Infallible to be the one that we mentioned, and that is the Imam. We have proved that the Imam is not but Infallible, and we have shown that if Infallibility is necessary to be in the Imam, there is no escape from that the Prophet, Allah’s blessings be upon him and his Family, to have confirmed his case, because Infallibility is not in the apparent disposition by which it is recognized by the creation through observation. Hence, it is obligatory that it is affirmed by the Knower of unseen things, Blessed and Exalted is He, on the tongue of His Prophet, Allah’s blessings be upon him and his Family, and that is because the Imam is not but affirmed of. The affirmation has been authenticated to us, in accordance to what we have clarified of arguments and what we have narrated of authentic reports.