Read this first.
A common objection raised (by Aḥmad Riḍā Khān himself and then his followers) against this passage of Ḥifẓ al-Īmān* is that for endowing the title “‘Ālim al-Ghayb” for creation (based on knowledge of ghayb acquired via a means), Maulānā Thānawī only allows for two possibilities or options: ba‘ḍ ‘ulūm ghaybiyyah (partial knowledge of ghayb) or tamām ‘ulūm ghaybiyyah (complete knowledge of ghayb). It is as though he does not allow for anything in between for virtue or excellence in knowledge of ghayb.
This objection emanates from a misunderstanding of what Maulānā Thānawī was trying to achieve. His purpose was not to discuss at what point a person will be deserving of virtue or excellence. Rather, his purpose was to deter his readers from using the title “‘Ālim al-Ghayb” for any creature, as in Sharī‘ah it is a term exclusive to Allāh. He first explains that “‘Ālim al-Ghayb” is a term applied exclusively to a being who has knowledge of ghayb independently. Hence, to use the term for those who have knowledge of ghayb via a means is a misuse and misapplication. Then, in relation to using the term ghayb for unseen knowledge acquired via a means, he presents the argument found in the passage in question.
The objection raised against this passage will be answered briefly below.
Ghayb is a maṣdar (verbal noun). A maṣdar in principle refers to a single entity (fard), as stated in Nūr al-Anwār (المصدر الذي هو فرد). A single entity can either be literally a single entity (fard ḥaqīqī) or in terms of consequence (fard ḥukmī). The latter refers to the entirety of the thing, because the entirety of a thing in relation to other things is like a “single entity” although in and of itself it is many things put together.**
Hence the term “ghayb” mentioned in “‘Ālim al-Ghayb” either refers to any part of ghayb (which in this context means unseen knowledge received via a means) or it means every single thing from ghayb. If it is the first meaning that is meant, this is not unique to the Prophet (ṣallallāhu ‘alayhi wasallam). Based on this, everyone will be entitled to be called “‘Ālim al-Ghayb”! In other words, based on this meaning, it would not be accurate to say the term can be limited to the Prophet (ṣallallāhu ‘alayhi wasallam), as based on this meaning, another person can just as well claim it can be used for himself. And if it is the second meaning that is meant (i.e. complete ghayb), this is discounted for the Prophet (ṣallallāhu ‘alayhi wasallam) by textual and rational evidences.
This in a nutshell is Maulānā Thānawī’s argument. As one can see, there is nothing problematic in this at all.
* The following passage:
“Further, if according to the statement of Zaid it is correct to apply the ruling of ‘ilm al-ghayb on the blessed person [of Rasulullah (sallallahu alaihi wasallam), based on which he will be called “‘Ālim al-Ghayb”], then he will be asked: Is the intent of this ghayb some ghayb or all ghayb? If some unseen knowledges are intended what then is the distinction of the Prophet (sallallahu alaihi wasallam) in this? Such knowledge of ghayb [i.e. some ghayb as opposed to all ghayb] is acquired by Zaid, Amr, indeed every child and madman, and indeed all animals and beasts, since each individual knows something or another that is hidden to someone else. Thus, everyone should be called “‘Ālim al-Ghayb”!”
** So, for example, the scholars of Uṣūl state that the maṣdar “ṭalāq” (divorce) can refer to a single ṭalāq or to triple-ṭalāq, because the latter is the maximum number of ṭalāqs and thus is a single entity in terms of consequence. It cannot refer to two ṭalāqs, however.