It is the ascent to higher levels. This is, in the matter of tawhid (the oneness of God), not regarding anything as proof, in the matter of tawakkul (reliance upon God) not regarding anything as a cause, and in salvation not seeing anything as a means. Thus, a person, by putting judgment, knowledge, and everything in their proper place, and by realizing that these are only tied to specific times and hidden within forms by Him, witnesses that the Real (al-Ḥaqq), Exalted is He, precedes all things. One actualizes the recognition of causes, and embarks upon the path of removing contingency (ḥadath). This tawhid, which is validated by the knowledge of fanāʾ (annihilation in God), purified in the knowledge of jamʿ (union), draws the people of jamʿ to tawhid, and is the tawhid of the khawāṣṣ (the elect).
The third type of tawhid is the tawhid of those whom the Real, Exalted is He, has made unique to Himself and worthy of His rank. His rank, as a radiance from Him, has illuminated the secrets of the group that comes from His purity, rendering them mute regarding His attributes, and leaving them powerless in the face of the spread of that radiance. With that radiance, He is indicated by the tongue of those who point to Him, which is the removal of contingency and the affirmation of pre-eternity (qidam).
There is a cause (ʿilla) over the symbol in this tawhid: this tawhid is only valid when that cause is removed. This, according to the words of the scholars of this path, is the center of indicating Him. (Manāzil, 47)
As this tawhid is adorned with attributes and divided into parts, the subtlety in expression, the excess in attributes, and the difficulty in its expansion increase (the more it is explained, the less it is understood). Only those who are people of spiritual discipline (riyāḍa), and those who possess ḥāl (spiritual state) and maqām (spiritual station), can ascend to this tawhid. Only those who are people of reverence can intend it, and those who can speak about the ayn al-jamʿ (the essence of union) can be occupied with it. Regarding this tawhid, allusions are erased, tongues become mute, and no expression can indicate it. Tawhid is beyond what the created points to, what the attainer is occupied with, or what the cause diminishes. In the past, to someone who asked me about the tawhid of the Sufis, I replied with these three verses:
No one has performed tawhid
except the One (al-Wāḥid)
for whoever besides Him
has engendered
has denied Him
for the one who speaks of His attributes
his tawhid
is nothing but the negation of the attributes of the One
It is only His own tawhid of Himself
but the description of Him by the describer
Allah knows best. (Manāzil, 48)
There are four levels of tawhid. Tawhid is divided into the essence, the essence of the essence, the shell, and the shell of the shell. To make this clearer for those whose understanding is weak, let us give an example: a walnut has an outer shell, an inner shell, and a kernel. The kernel also has oil, which is the essence of the essence.
In this ḥāl (spiritual state), the first level of tawhid is for a person to say with his tongue “Lā ilāha illā Allah” without being aware of its meaning or by denying it. This is the tawhid of the hypocrites. The second level is for the heart to affirm the meaning of what the tongue utters. Indeed, all Muslims have affirmed this. This is the belief of the common people (ʿawāmm).
The third level is to witness that meaning through the light of the Real, that is, through unveiling (kashf). This is the station of the muqarrabūn (those brought near). When they look, they see many things, but they know that all these many things emanate only from the One, the Subduer (al-Qahhār), Allah.
The fourth level of tawhid is to see nothing in existence but the One. This is the witnessing of the ṣiddīqūn (the truthful). The Sufis call this fanāʾ fi’l-tawhid (annihilation in tawhid), for since he sees nothing but the One, he does not see himself. Such a person, being drowned in tawhid, does not see himself, and thus annihilates himself in his tawhid. That is, he becomes annihilated from seeing both himself and creation.
The muwaḥḥid (person of tawhid) at the first level is only a muwaḥḥid with his tongue. Such tawhid only protects its possessor in this world (dunyā) from the sword and spear of the sharia (the sacred law) (i.e., by being Muslim, his life is secured).
The muwaḥḥid at the second level believes with his heart what his tongue says, and his heart does not belie what he believes. This is an unbreakable knot upon the heart. However, if this person dies with that iman (faith) without loosening this knot through sins, that iman will protect him from punishment in the Hereafter. There are some things that loosen and untie this knot of iman, which are called innovations (bidʿa). Just as there are things that loosen and untie the knot of iman, there are also things that protect it from being loosened and untied, that strengthen it and bind it to the heart; this is called kalām (theology), and the one who knows kalām is called a mutakallim.