Imaam Ibn Al-Jawzee (d. 597H, rahimahullah) said:
“Then a group of people – i.e. from the Sufis – came and began to speak to them concerning hunger, poverty, whisperings and notions. And they authored books on these subjects, as was the case with Al-Haarith Al-Muhaasibee.
Then another group of people came (afterward) that revised the way of Sufism, characterizing it with attributes by which they distinguished it (from its original state), such as: wearing old tattered clothes, hearing (music), bursting out in passionate emotions, dancing and clapping. And they particularized themselves by exceeding in cleanliness and purification.
Then this matter (Sufism) continued to flourish, and their shaikhs began to fabricate stories for them and speak about their mystical occurences. This affirmed their view that what they were upon was the most complete forms of knowledge, such that they named it the hidden knowledge (al-‘ilm-ul-baatin), while making knowledge of the Religion, apparent knowledge (al-‘ilm-ud-dhaahir).
Among them were those whose severity in hunger brought them to fancy corrupt notions. So they would claim strong love and passion for the truth. It was as if they imagined a figure with a beautiful appearance and thus fell madly in love with it. These individuals linger between disbelief and innovation.
Then these people divided into various orders and their beliefs grew corrupt. So among them were those who held the view that Allaah is incarnate in His creation (hulool), and those who held that view that the Creator and creation were in reality one existence (Ittihaad)!
And the Devil did not stop speaking to them about different types of innovations until they made them into aspects of the Sunnah.
Then there came Abu ‘Abdir-Rahmaan As-Sulaamee who wrote a book for them called ‘as-Sunan’. He also compiled a book for them called ‘Haqaa’iq-ut-Tafseer’, in which he mentioned amazing things about them (i.e. Sufis) concerning their interpretation of the Qur’aan, based on the (mystical things) that occurred to them, without tracing that back to any of the sources where knowledge is derived from. And indeed, what brought them to take such things and place them as their views was their state of daze, due to their strict abstinence of food and their love for talking at great lengths of the Qur’aan.
Abu Mansoor ‘Abdur-Rahmaan Al-Qazaaz informed us that: Abu Bakr Al-Khateeb informed us, saying: Muhammad ibn Yoosuf Al-Qattaan An-Naisaburee said to me: ‘Abu ‘Abdir-Rahmaan ‘As-Sulamee is not reliable. He was not able to hear anything except for a few sounds, due to deafness. So when the ruler Abu ‘Abdillaah bin Al-Bay’ died, he began to narrate hadeeth on the authority of Al-A’saam from Taareekh Yahyaa bin Ma’een as well as other books besides it. And he would fabricate ahaadeeth for the Sufis.”
Abu Nasr As-Siraaj wrote a book for them called ‘Lum’us-Soofiyyah’ in which he stated horrendous beliefs and hideous statements that we will mention later in more details, by the Will of Allaah.
And Abu Taalib Al-Makkee wrote the book Qoot-ul-Quloob in which he mentioned fabricated ahaadeeth and narrations that cannot be traced back to any source with regard to the subject of prayers during the days and nights and other subjects. He also mentioned false doctrines in it and constantly repeated statements such as: “Some of the mukaashifeen (those to whom Allaah has disclosed secrets of hidden realities) have stated…’ These types of words are empty and pointless. He also mentions in it, relating from some Sufis, that Allaah reveals aspects of hidden matters to his ‘saints’ in this world.
Abu Mansoor Al-Qazaaz informed us: Abu Bakr Al-Khateeb informed us, saying: Abu Taahir Muhammad bin al-‘Ullaaf said: ‘Abu Taalib Al-Makkee entered the city of Basrah after the death of Abul-Husayn bin Saalim and ascribed to his views. Then he traveled to Baghdad and the people gathered around him in the place of admonition to hear from him. So he began to speak but got confused and began to mix up his words. It was memorized from him that he said: ‘There is nothing more harmful to the creation than the Creator.’ So the people declared him an innovator and deserted him completely. Afterward, he was prevented from speaking to the people.’
Al-Khateeb said: ‘Abu Taalib Al-Makkee wrote a book in the language of the Sufis called Qoot-ul-Quloob in which he mentioned many horrendous and repugnant things concerning Allaah’s Attributes.'”
Then there came Abu Nu’aim Al-Asbahaanee who wrote a book for them called ‘Hilyat-ul-Awliyaa’ (“The Beautification of the Saints”), in which he mentioned many evil and despicable things on the laws of Sufism. And he had no shame in stating that Abu Bakr, ‘Umar, ‘Uthmaan and ‘Alee, as well as the rest of the high ranking Companions, were from among the Sufis! So in this book, he spoke of amazing things that occurred to them. He also mentioned Shuraih Al-Qaadee, Al-Hasan Al-Basree, Sufyaan Ath-Thawree and Ahmad bin Hanbal as being from among them (i.e. the Sufis). Similarly, in ‘Tabaqaat-us-Soofiyyah’, As-Sulamee mentioned Fudayl (bin ‘Iyyaad), Ibraheem bin Adham and Ma’roof Al-Karkhee as being from among the Sufis, by pointing out that they were individuals who abstained from the worldly life and its luxuries (zuhd).
Sufism is an ideology that is well known for exceeding in abstinence of worldly luxuries (zuhd). What shows the difference between them (and the Sufis) is that no one ever condemned abstinence (zuhd), whereas Sufism was condemned because of what we will mention later.
‘Abdul-Kareem bin Hawaazin Al-Qushayree wrote a book for them called ‘ar-Risaalah’, in which he mentioned many far-fetched and mystical things such as talk on al-fanaa (annihilation) and al-baqaa (subsistence), al-qabd (contraction), al-bast (expansion), al-waqt (the moment), al-haal, al-wajd (finding) and al-wujood, al-jam’ (union) and tafaruqqah (separation), as-sahu (clarity) and as-sakr (drunkenness), adh-dhawq (taste) and ash-sharab (drink), al-mahu (effacement) and al-ithbaat (affirmation), at-tajallee (manifestation) and al-muhaadarah (presence), al-mukaashafah (unveiling) and al-lawa’ih, at-tawaali’ and al-lawaami’, at-takween and at-tamkeen, ash-sharee’ah and al-haqeeqah (Reality), and other insanities that do not amount to anything. And his tafseer is even more bizarre than this!
Then there came Muhammad bin Taahir Al-Maqdisee who wrote Safwat-ut-Tasawwuf (“The Perfection of Sufism”) for them, in which he stated things that any person with common sense would feel ashamed to mention! We will mention what is proper from its subjects later, by the Will of Allaah.
Then there came Abu Haamid Al-Ghazaalee who wrote the book Ihyaa ‘Uloom-ud-Deen for them, according to the methodology of the (Sufi) people, which he filled with baseless ahaadeeth even though he knew well they were baseless. He spoke about knowledge of the Mukaashafah (unveiling of unseen by Allaah to Sufis) and withdrew form the principles of Fiqh. And he stated such things as: ‘Indeed the stars, the sun and the moon, which Ibraheem saw, were in fact lights that screened Allaah!’ Such things are not mentioned in any of the sources of knowledge. Rather, this is from the types of speech of the Baatiniyyah.
He (Al-Ghazaalee) also said in the book ‘Al-Mufsih bil-Ahwaal’: ‘While in their state of wakefulness, the Sufis are able to witness the angels and souls of the prophets, hear their voices and take hold of benefit from them. Then this condition escalates from the witnessing (of their) images to levels in which they are contained within these domains.'”
The factors that caused these individuals to write these books was their little knowledge of the Sunnah, Islaam and the narrations, as well as their dedication for that they approved of from the way of the people (Sufis). They only approved this way because of adoration for abstinence (zuhd) that was established in their souls. They did not see any condition better than the condition of these people (Sufis) in regards to appearance, nor any speech more pleasant that their speech, whereas in the biographies of the Salaf, they found a form of harshness. So the people inclined very strongly towards these individuals (Sufis).
This was due to what we stated previously, that it was a way, which was characterized outwardly by cleanliness and worship, whereas on the inside, it was about indulging in leisure and hearing music, which the bodily dispositions incline to. The original Sufis would flee from the leaders and authorities. However (in later times) they became friends.
The majority of these books that were compiled for them have things in them that cannot be traced back to any (authentic) source. Rather, they are only based on mystical occurrences that befell some of them, which they managed to take hold of and record. They called this hidden knowledge (al-‘ilm-ul-baatin). Abu Ya’qoob Ishaaq bin Hayya said: ‘I heard Ahmad bin Hanbal once when asked about the occurrence of delusions and notions, so he replied: The Sahaabah and the Taabi’een never spoke about such things.'”
Source: Talbees Iblees (pg. 162 and on) with the verification of Mahmood Mahdee Al-Istanbulee. Taken from the book, The Methodology of Ahlus-Sunnah wal-Jamaa’ah on criticizing Individuals, Books & Groups, by Shaykh Rabee’ bin Haadee Al-Madkhalee, Al-Ibaanah Publishing, pp.193-199.
 These are names for Sufi concepts and beliefs. Some of them have been defined as such:
Fanaa (Annihilation): A state in which the mureed (Sufi) becomes so absorbed in dhikr (remembrance of Allaah) that he becomes unaware of himself and his surroundings and is at tranquility with the remembrance of his Lord, negating or annihilating his self.
Bast (Expansion) and Qabd (Contraction): refer to the various degrees of relative union and separation from the Creator.
Baqaa: The consciousness of survival in Allaah.
Waqt (Time): The moment in which someone becomes conscious of the reality and the Creator; the mureed is neither in the past or the future.
Mukaashafah (Unveiling): The state in which the Truth (Allaah) and the Unseen become revealed to the Sufi.
Tajallee (manifestation): The state in which Allaah manifests revelation to the Sufi.
Sakr (Drunkenness): A state in which the mureed is absorbed in the hidden matters to the point that the common person cannot understand him.
Wajd (Finding): State of ecstasy in which the Sufi finds the realization and presence of Allaah, usually after hearing (Samaa) dhikr.
Jam’ (Union): A state in which the Sufi only sees the Truth (Allaah) without the creation.
Muhaadarah (Presence): Being in the presence of Allaah.
Tafarruqah or Farq (Separation): When the Sufi in the state of Fanaa sees the creation (i.e. himself), the opposite of Jam’.
And Allaah knows best.