[On “Ladunni” Knowledge through Inspiration]

Answer – and Allah is the One who grants success and help: Allah, glorified and exalted is He, created the human being in general, when He created him and brought him out from his mother’s womb, ignorant; then He placed for him the means by which he attains knowledge, and then He charged him with acquiring knowledge. This is the way (sunnah) of Allah in His creation, exactly as He, majestic is His affair, said: "And Allah brought you out of the wombs of your mothers while you knew nothing, and He made for you hearing, sight, and hearts..." [an-Nahl:78].
So the acquisition of knowledge of the revealed laws (sharā’i‘) is only by means of these avenues – prophets and others being equal in that. From here Allah, exalted is He, said addressing our Prophet (May Allah bless him and his family and grant them peace): "And He found you lost, and guided you" [ad-Duha:7], and He said: "And you did not know what the Book is, nor [what] faith is" [ash-Shura:52], and His saying: "And He taught you that which you did not know" [an-Nisa’:113]. The prophets and messengers (Peace be upon them) are the most elevated of humankind in status with Allah, the highest of them in rank, and the closest of them in nearness to Him; yet they did not come to know the laws of Allah and His rulings except by Allah teaching them, as Allah, exalted is He, has related to us in His Noble Book. Likewise the angels who are near [to Allah] do not attain knowledge except by way of learning. From here Allah, exalted is He, related to us the words of the angels: "Glory be to You, we have no knowledge except what You have taught us. Indeed, it is You who are the All-Knowing, the All-Wise" [al-Baqarah:32]. It thus becomes clear to us, by what we have mentioned, that the claim of those who assert “ladunnī knowledge” for certain people is a false claim, belied by the Qur’anic proofs.
Furthermore, it has reached us that some of them claim and say: that the Imam knows the unseen, or something of the knowledge of the unseen, and that a person is not an Imam unless he is such. This claim, like the one before it, is a false claim, falsified by the proofs of the Qur’an, such as His saying, exalted is He: "Indeed, Allah [alone] has knowledge of the Hour, sends down the rain, and knows what is in the wombs. And no soul knows what it will earn tomorrow, and no soul knows in what land it will die. Indeed, Allah is All-Knowing, All-Aware" [Luqman:34]; and His saying, exalted is He: "And Allah would not inform you of the unseen, but Allah chooses of His messengers whom He wills" [Al ‘Imran:179]; and His saying, exalted is He, relating from the Prophet (May Allah bless him and his family and grant them peace): "If I had knowledge of the unseen, I would have acquired much good, and harm would not have touched me. I am only a warner…" [al-A‘raf:188]; and His saying, exalted is He: "And with Him are the keys of the unseen; none knows them except Him. And He knows what is on the land and in the sea. Not a leaf falls but that He knows it…" [al-An‘am:59]; and His saying, exalted is He: "Knower of the unseen – and He does not disclose His unseen to anyone, except whom He has approved of messengers…" [al-Jinn:26–27]; and His saying, exalted is He: "He is Allah, there is no deity except Him, Knower of the unseen and the witnessed…" [al-Hashr:22]; and His saying, exalted is He: "Knower of the unseen and the witnessed, the Most Great, the Most High" [Yusuf:53 or ar-Ra‘d: 9, intended verse]; and His saying, exalted is He: "Say, ‘None in the heavens and earth knows the unseen except Allah’" [an-Naml: 65].
Yes, Allah, exalted is He, may grant some of His servants an increase in intellect, support him with understanding, and aid him in reaching what is correct; so he derives, by his understanding and his intellect, from the Qur’an legal rulings which other scholars may not be enabled to derive and extract. Likewise Allah, exalted is He, guides him and grants him success in knowing the sound Sunnah and distinguishing it from other than it, then in extracting legal rulings from it and deriving them. This is the reality of His saying, exalted is He: "And those who are guided – He increases them in guidance and gives them their righteousness" [Muhammad:17], and His saying: "If you fear Allah, He will grant you a criterion" [al-Anfal:29].
As for the claim that the Imam knows the legal rulings without reflection and derivation from the Book of Allah, exalted is He, and the Sunnah of His Messenger (May Allah bless him and his family and grant them peace), then it is a false claim; likewise the claim that he knows the unseen. This is the blameworthy exaggeration (ghuluw) in the religion of Islam. The Commander of the Faithful (Peace be upon him) said: “Two [types of people] will perish concerning me: an exaggerating lover and a hateful enemy…” and so it was: a people exaggerated regarding him (Peace be upon him) until they made him a lord, and a people hated him and disparaged him until they cursed him – rather, they made cursing him a “sunnah”. Upon them be the curses of Allah.
Likewise, a people exaggerated concerning the Ahl al-Bayt (Peace be upon them) until they claimed for them knowledge of the unseen, and that they know without learning, and that they are infallible, and that they… and so on.

Source: Min Thimār al-ʿIlm wa al-Ḥikmah vol.3