The Knowledge of the Book
Abu Said al-Khudri: I asked the Messenger of Allah (S.A.W.) about the noble Ayah, "And such as have knowledge of the Book" (13:43). His Holiness (S.A.W.) replied: It implies my brother Ali ibn Abi Talib.
Imam al-Baqir (A.S.): What is the concept of the noble Ayah "Say: Enough for a witness between me and you is Allah, and who has knowledge of the book" (13:43) is us [the Ahl al-Bayt]. Ali (A.S.), next to the Holy Prophet (S.A.W.), is the first, the superior, and the best of us all.
Abu'l Hasan Muhammad ibn Yahya al-Farsi: One day Abu Nuas encountered Abul Hasan Ali ibn Musa al-Reza (A.S.) while his Holiness (A.S.) was riding on a mule returning from al-Ma'mun.
Abu Nuas approached him, greeted and said: O son of the Holy Prophet (S.A.W.)! I have written down some couplets concerning you and I request you to hear them from me. His Holiness (A.S.) said: Take out what you have written. Then he read as follows: These are the pure ones whose garments are clean, and when they are recalled, greetings will be sent to them. Whoever is not an Alawi in his relation does not have an honor from the ancient time.
When Allah created the creatures and organized them, O Mankind! He picked you out and selected.
You are the superior species and with you are the knowledge of the Book and what the chapters of the Qur'an have brought down. Imam al-Reza (A.S.) said: You cited couplets which nobody has taken precedence of you in composing.

Ta'wil of the Holy Qur'an
The Messenger of Allah (S.A.W.): After me [after my demise] Ali will teach people the ta'wil of what they do not know of the Holy Qur'an.
Imam Ali (A.S.): Ask me about the Book of Allah, the Almighty, that by Allah there has not been revealed a verse of it at night or in the daytime, on the way or somewhere, except that the Holy Prophet (S.A.W.) taught me reading it as well as its Ta'wil. Ibn al-Kawwa' asked: O Amir al-Mu'minin! What do you say about the verses revealed to the Holy Prophet (S.A.W.) when you were not present? The Imam(A.S.) replied: When I was not present, the Holy Prophet used to memorize the verses revealed to him so that when I took audience with him the Prophet would teach me its reading and would say: O Ali(A.S.)! After you left, Allah revealed these verses to me and their Ta'wil is so and so. Thus he would teach me on their Revelation (Tanzil) and Ta'wil. Imam al-Baqir (A.S.): Nobody but successors can claim that he knows the Holy Qur'an completely, neither the exterior nor the interior.
Abu al-Sabbah: I swear by Allah, al-Imam Jafar al-Sadiq(A.S.) told me: Allah taught the Revelation and Ta'wil to His Holy messenger(S.A.W.) and the Holy Prophet (S.A.W.) taught it to Ali(A.S.) and he, I swear by Allah, taught it to us.

Allah's Grand Name
Imam al-Baqir(A.S.): Allah's grand name has seventy three letters and Asif only know one of out those letters so that when he uttered it the earth devoured what was between him and the throne of Bilqis (Queen of Sheba) and Asif was able to take the throne with his hand; then in less than a blink of an eye the earth turned back into its former shape. And seventy two letters of the grand name are with us and one secret letter is with Allah the Almighty which He has by His prescience dedicated to Himself; and there is no power and might except with the Exalted and Almighty Allah.

Familiarity with all Languages
Abu Baser: I said to Imam Kazim (A.S.): I may be sacrificed to you, how is an Imam recognized? He replied: By certain characteristics.
The first of them is that there has already been a reference to him by his father, so that this may be a proof to people. He is asked and he replies and if they are silent in a certain instance he proceeds to talk (and gives the answer to the question they have had in mind) and he foretells about future and speaks to people in any language necessary. Then he said to me: O Aba Muhammad! Before you stand up I let you know of a sign. Shortly afterwards, a man from Khurasan entered upon us. He talked to the Imam in Arabic, and the Imam answered him in Persian. The man from Khorasan said to the Imam: I may be sacrificed to you, by Allah what impede me from talking to you in Persian was that I supposed you do not speak it well enough. The Imams (A.S.) said: Glory be to Allah! If I could not answer you all right, then what would my superiority be over you? Then he said to me: O Aba Muhammad! None of the people's speech nor that of any bird or animal or every living thing is hidden to the Imams. Anyone who does not have these characteristics is not an Imam.
Abu Hamza Nasir, the retainer of the Imam: I frequently heard al-Imam al-Askari (A.S.) speak to his retainers in their own languages, including Turkish, Roman, and Slavic. I got bewildered and asked: This man has been in Madinah and was not shown up until the demise of Abul Hasan(A.S.); nor has anybody seen him, how is this possible? I was talking to myself when his Holiness (A.S.) came toward me and said: The Exalted and Almighty Allah has distinguished His hujjah from His other creatures in every aspect and has bestowed on him the familiarity with various languages and genealogy and death moments and other happenings, otherwise there would have been no difference between the hujjah and those over whom the hujjah is appointed and incumbent.
Familiarity with the Language of the Birds and Any other Animal Imam Ali (A.S.): Like Solomon, the son of David, we too are acquainted with the language of the birds and any sea and land animal. Imam Ali (A.S.): We have become familiar with the language of the birds and enjoyed everything which is in itself a great virtue.

Awareness of What Has Been and Will Be
Imam Ali(A.S.): Had there not been a verse in the Book of Allah, I would have informed you about what has existed and will exist until the Day of Resurrection; and that noble verse is as follow: "Allah doth blot out or confirm what He pleaseth; with Him is the Mother of the Book" (13:39).
Sayf al-Tammar: Together with a group of the Shias, we were in the company of al-Imam al-Sadiq (A.S.) in Hijr. His Holiness (A.S.) said: I swear to the Lord of Kabah and the House of Allah-repeating it three times-that if I were with Moses and Khidr, I would tell that I was more learned than them, and would inform them of the things they did not have access to, since Moses and Khidr had been given awareness of the past and not of the present and the future up to the Resurrection Day; whereas we have inherited such awareness from the Holy Prophet(S.A.W.) in a perfect manner.
Imam al-Reza (A.S.): Is it not true that Allah says: "He (alone) knows the unseen, nor does He make anyone acquainted with His mysteries, except a Messenger whom He has chosen" (72: 26,27) and the Holy Messenger(S.A.W.) is Allah's chosen one and we are inheritors of the Holy Prophet(S.A.W.) whom Allah lets know of whatever of His mysteries that He wishes, and he has taught us of what ever that has been and will be until the Resurrection Day?

Awareness of Mortalities and Calamities
Imam Ali (A.S.): We from a family whose members are taught awareness of mortalities, calamities and genealogies: I swear by Allah if one of us stands at a bridge and this nation parade before him he will tell them their names and lineage.
Imam al-Reza (A.S.)- in a letter to Abd Allah ibn Jundab-: And then, Muhammad (S.A.W.) was Allah's trustee among the people and when he passed away we, the Ahl al-Bayt, became his inheritors and now we are Allah's trustees on the earth and are aware of mortalities and calamities and the genealogies of Arabs and the birthplace of Islam is with us.

Awareness of what is in the Heavens and on the Earth
The Messenger of Allah (S.A.W.): No bird's wings will flap in the air of which we are not aware.
Abu Hamzah: I heard al-Imam al-Baqir(A.S.) say: Nay, I swear by Allah, it is never likely that a scholar be ignorant, having knowledge on something and being ignorant on another. Then he said: Allah is too Great, Noble, and Honorable to ordain as obligatory the obedience of a servant [the Imam] who is not aware of the heavens and the earth. Then he added: These are not hidden to him [the Imam].

Awareness of what Allah Creates at Night and Daytime
Salama ibn Muhriz: I heard al-Imam al-Baqir (A.S.) say: Among the sciences that are granted to us are the interpretation of the Holy Qur'an and its ordinances, the science of changes of time, and its adversities. Whenever Allah wills goodness for a folk He makes them hear it and if someone fails to hear he turns his face away as if he has not heard at all. The Imam(A.S.) remained silent for a while and then said: If we found a confidant [of our secrets] or a trusted person we would certainly tell him (the truths), and it is Allah that all are seeking assistance from.
Humran ibn A'yan: I said to al-Imam al-Sadiq (A.S.): Are Torah and Bible and Psalm and whatever existed in the early Scriptures, namely, those of Ibrahim and Musa with you? The Imam (A.S.) said: Yes. I asked: Is it the very Great knowledge (al-Ilm al-Akbar)? He replied: O Humran, yes if it were restricted to this, but our knowledge to what Allah brings up at night and in daytime is greater.

Source: Ahl al-Bayt (A.S.) in the Holy Qur'an and Hadith
By: Ayatullah Muhammadi Rayshahri