The view of the righteous predecessors and the vast majority of the jurists is that the Imaan of the blind follower is valid.
An-Nawawi said, “His saying ? in the other narration; “I fight the people until they testify that there is no deity worthy of worship except Allah, and they believe in me and what I have come with…” [327] Reported by Muslim (21) from the hadeeth of Abu Hurayrah (may Allah be pleased with him) is an explicit evidence for the position of the scholars and the majority of the righteous predecessors and those who came after them, that if a person firmly believes in the religion of Islam with there being no hesitance in them, then that suffices them, and they are a believer from the monotheists. And it is not obligatory upon them to learn the proofs of the dialectic theologians (scholars of Kalaam) nor to come to know Allah the Exalted through them, contrary to what was said by those who obligated that and made it a condition for being from the people of the Qiblah, and claimed that they cannot have the rulings of Muslims except through it, which is the position of a lot of the Mu’tazilah and some of our companions from the dialectic theologians (scholars of Kalaam), and it is a clear error. For what is required is a firm belief and affirmation, and that has been attained, and because the Prophet ? was content with affirmation of what he ? came with and did not make knowledge of the evidence a condition for the acceptance of Faith. For this has been made apparent by multiple hadeeths in the two authentic collections, the combination of all affirming this principle would reach the level of Tawaatur (mass transmission that leaves no doubt about is authenticity and certainty), and also makes it absolute and definite knowledge.” [328] “al-Minhaj Sharh Saheeh Muslim Ibn al-Hajaj” (1/210)
Ibn Taymiyyah said, “As for the imitation that is invalid and blameworthy, then it is to accept someone else’s speech without any proof. Allah, Most High, says: And if they are told “Follow that which Allah has revealed”, they say “Rather we will follow what we found our forefathers upon.” Even though their fathers did not know anything nor were they guided? Therefore, this following and imitation is that which Allah censures; the following of desires, whether it is done out of habit and lineage such as following ones’ forefathers, or due to positions of leadership such as following the elites, leaders, and the arrogant. This is similar to a man imitating his father, or his leader, or someone who holds power over him… And Allah has made clear that what is obligated is to leave off this type of imitation, and to follow what Allah has revealed to His Messengers, for they are the proof of Allah by which He manifests Himself to His creation… So if they know that the one they imitate is upon the truth, such as imitating the Messenger, or the people of consensus, then they have imitated them with proof, namely knowledge that they are from the people of knowledgeable, and it is not the blameworthy imitation mentioned before, rather this form of imitation is obligated, due to the knowledge that the Messenger is infallible, and that the people of consensus are likewise infallible in their consensus.” [329] “Majmoo’ al-Fataawa” (20/15)
Some of the people of knowledge mentioned that the obligation of Imaan in Allah, His angels, His Books, His Messengers, and the Last Day, is not conditioned with attaining them through observation and deductive reasoning. Rather a firm belief in them is sufficient. The chosen view of the righteous predecessors, the Imams of fatwa who came after them, and the vast majority of the jurists, is the validity of the Imaan of the blind follower. This is because the Companions (may Allah be pleased with them) were the ones who conquered most of the lands of the non-Arabs, and they accepted the Imaan of their laypeople, similar to what they did to the untamed from among the Arabs, even when their Islam was professed under the threat of the sword, or out of merely following their leaders who had embraced Islam. The Companions never commanded anyone of them to make observations and rational deductions to affirm their Faith, nor did they ask them for proof of their affirmation, nor did they defer them until they completed their observations and reflections. Thus, it becomes obvious to the sensible that those people were never commanded to reflect or observe any evidence before having their Islam accepted. In fact, it was impossible for this to be done under the circumstances of that point of time. As such, the action of the Companions (may Allah be pleased with them) who accepted the Islam of people without demanding them to investigate and observe evidence is evidence that supports the position that affirms the Imaan of the one who merely imitates. [330] “Lawami’ al-Anwar al-Bahiyyah” – as-Safarini (1/270)