Imam Ibne Taimmiya Ibn Qayyim views Sufism Tasawwuf,Fatawa Manazil as-Sa'ireen

Imam Ibn Taymiyya (661 - 728 AH) views on Tasawwuf/Sufism

1. "Tasawwuf has realities and states of experience which they talk about in their science. Some of it is that the Sufi is that one who purifies himself from anything which distracts him from the remembrance of Allah and who will be so filled up with knowledge of the heart and knowledge of the mind to the point that the value of gold and stones will be the same to him. And Tasawwuf is safeguarding the precious meanings and leaving behind the call to fame and vanity in order to reach the state of Truthfulness, because the best of humans after the prophets are the Siddiqeen, as Allah mentioned them in the verse:
"(And all who obey Allah and the Apostle) are in the company of those on whom is the grace of Allah: of the prophets, the sincere lovers of truth, the martyrs and the righteous; Ah! what a beautiful fellowship." (an-Nisa', 69,70)
"...some people criticised Sufiyya and Tasawwuf and they said they were innovators, out of the Sunnah, but the truth is they are striving in Allah's obedience [mujtahidin fi ta'at-illahi], as others of Allah's People strove in Allah's obedience. So from them you will find the Foremost in Nearness by virtue of his striving [as-saabiq ul-muqarrab bi hasab ijtihadihi]. And some of them are from the People of the Right hand [Ahl al-Yameen mentioned in Qur'an in Sura Waqi'ah], but slower in their progress.... And this is the origin of Tasawwuf. And after that origin, it has been spread and [tasha'abat wa tanawa'at] has its main line and its branches.  [Majmu'a Fatawa Ibn Taymiyya al-Kubra, Vol. 11, Book of Tasawwuf, p. 497].
2. "The miracles of saints are absolutely true and correct, by the acceptance of all Muslim scholars. And the Qur'an has pointed to it in different places, and the Hadith of the Prophet (s) has mentioned it, and whoever denies the miraculous power of saints are only people who are innovators and their followers." [al-Mukhtasar al-Fatawa, page 603]. 

3. Ibn Taymiyya says, "what is considered as a miracle for a saint is that sometimes the saint might hear something that others do not hear and they might see something that others do not see, while not in a sleeping state, but in a wakened state of vision. And he can know something that others cannot know, through revelation or inspiration." [Majmu'a Fatawi Ibn Taymiyya, Vol. 11, p. 314].

Ibn Qayyim (Student of Ibne Tamiyya) views on Tasawwuf/Sufism (691 - 751 AH.)

1."We can witness the greatness of the People of Sufism, in the eyes of the earliest generations of Muslims by what has been mentioned by Sufyan ath-Thawri (d. 161 AH), one of the greatest imams of the second century and one of the foremost legal scholars. He said, "If it had not been for Abu Hisham as-Sufi (d. 115) I would never have perceived the action of the subtlest forms of hypocrisy in the self... Among the best of people is the Sufi learned in jurisprudence." [Manazil as-Sa'ireen.]

1. It is known to all that on the name of Sufism so many bad people has entered and spreade Innovation on Graves and so many rituals. No one is supporting those deviated people on the name of Sufism. 

2. And Ulmae Haq and good Sufis themselves has always come up agaist innovations on the name of Tasawwuf.  

3.The person who gave death sentense to Mansur Hallaj was also a sufi Junaid Bughdadi.R.A. Although both were Sufi but when he Junaid R.A. felt something contradictory to Shariah he Gave death sentence.

4. Mujaddid Alfasani R.A ,Syed Ahmad Shaheed, Syed Ismaeel Shaheed R.A also were Sufis but strived against wrong practices on the name of Tasawwuf, and made it pure and according to Quran and Sunnah. )