Imam Ibn Taymiyya mentions in the volume already cited, page 190: "A servant of Allah, Almighty and Exalted, cannot be considered a saint unless he is a true believer. Allah mentions in Qur'an, Surat Yunus, 62-63: "Now surely, on the friends of Allah there is no fear, nor shall they grieve; those who believe and guard against evil."
He then quotes the famous hadith from Bukhari: "My servant draws not near to Me with anything more loved by Me than the religious duties I have enjoined upon him, and My servant continues to draw near to Me with supererogatory works so that I shall love him. When I love him I am his hearing with which he hears, his seeing with which he sees, his hand with which he strikes and his foot with which he walks. Were he to ask [something] of Me, I would surely give it to him, and were he to ask Me for refuge, I would surely grant him it. I do not hesitate about anything as much as I hesitate about [seizing] the soul of My faithful servant: he hates death and I hate hurting him."
He explains the phrase, "Whoever comes against one of My saints is challenging Me to fight" thus: "It means that Allah is expressing: 'I will seek revenge against anyone who comes against My saints like an aggressive lion.'" (p. 314)
"It is said that after the Seal of Prophets (s), revelation does not descend upon anyone else. Why not? In fact it does, but then it is not called 'revelation.' It is what the Prophet (s) referred to when he said, 'The believer sees with the Light of God.' When the believer looks with God's Light, he sees all things: the first and the last, the present and the absent. For how can anything be hidden from God's Light? And if something is hidden, then that is not the Light of God. Therefore the meaning of revelation exists, even if it is not called revelation."
From Rama's Fihi ma fihi.
Ibn Taymiyya continues in the same book, Majmu'a Fatawi Ibn Taymiyya: "What is considered as a miracle for a saint is that sometimes the saint might hear something that others do not hear or see something that others do not see, not while asleep, but in a wakened state of vision. He can know things that others cannot know, through revelation or inspiration."
In another book, Mukhtasar al-Fatawa al-Masriyya, published by al-Madani Publishing House, 1980, page 603, he writes: "The miracles of saints are absolutely true and correct, and acknowledged by all Muslim scholars. The Qur'an has pointed to it in different places, and the Hadith of the Prophet (s) have mentioned it, and whoever denies the miraculous power of saints are innovators or following innovators."
He continues quoting the Prophet's saying about the saints: "You are the witnesses of Allah on earth."
He said (volume 11, page 313): "Allah Almighty will unveil to his saints states that have never been unveiled before and He will give them support without measure. If that saint begins to speak from the things of the unseen, past or present or future, it is considered from the viewpoint of Bab al-cilm al-khariq, miraculous knowledge. Anything that a saint does which is from the unseen, for people or for listeners, of healing or teaching knowledge, it is accepted and we must thank Allah for it."
In the volume entitled cIlm as-Suluk, ("The Science of Travelling the Way to God"), which consists of the entire 775 pages of volume 10 of Majmaca al-Fatawa, he says (p. 516): "The great Sufi shaikhs are well known and accepted, such as: Bayazid al-Bistami, Shaikh Abdul Qadir Jilani, Junaid ibn Muhammad, Hasan al-Basri, al Fudayl ibn al-Ayyad, Ibrahim bin al-Adham, Abi Sulayman ad-Daarani, Ma'ruf al-Karkhi, Siri as-Saqati, Shaikh Hammad, Shaikh Abul Bayan.
"Those great Sufis were the leaders of humanity, and they were calling to what is right and forbidding what is wrong."
At present we are in a position to go much further than saying that Ibn Taymiyya simply praised Sufism. We can say with definitiveness that he was an aspirant in the Sufi Way who belonged to more than one tariqat, primarily to the Qadiri Tariqat, of Shaikh Abdul Qadir al-Jilani.
In a unique manuscript of the H anbali Yusuf ibn cAbd al-Hadi (d. 909 H./1503 CE), entitled Bad' al-culqa bi labs al-khirqa, uncovered in the Princeton University Library, Ibn Taymiyya is listed in a Sufi spiritual genealogy with other well-known Hanbali scholars. The links in this genealogy are, in descending order from cAbdul Qadir Jilani:
Shaikh cAbdul Qadir Jilani (d. 561 H./1165 CE)
Abu cUmar b. Qudama (d. 607 H./1210 CE)
Muwaffaq ad-Din b. Qudama (d. 620 H./1223 CE)
Ibn cAli b. Qudama (d. 682 H./1283 CE)
Ibn Taymiyya (d. 728 H./1328 CE)
Ibn Qayyim al-Jawziyya (d. 751 H./1350 CE)
Ibn Rajab (d. 795 H./1393 CE)
Furthermore, there is another unique manuscript, also found in the Princeton Library, of the work of Ibn Taymiyya himself, in a book named, Targhib al-Mutahabbin fi labs Khirqat al-Mutammayyazan by Jamal ad-Dan al-Talyani. Here are Ibn Taymiyya's own words, as quoted from a work of his, al-Mas'ala at-Tabraziyya: "I wore the blessed Sufi cloak of Shaikh cAbdul Qadir Jilani, there being between him and me two Sufi shaikhs."
In another manuscript he said, "I have worn the Sufi cloak of a number of Sufi shaikhs, belonging to various tariqats, among them Abdul Qadir al-Jilani, whose tariqat is the greatest of the well-known ones, may Allah have mercy on him."
After him, the lineage continues on to his student, Ibn Qayyim al-Jawziyya, and his student Ibn Rajab.
The references for what we have mentioned are: "al-Hadi" manuscript in Princeton Library, Yahuda Collection, fol. 154a, 169b, 171b-172a; "at-Talyani," manuscript, Chester Beatty, 3296 (8) in Dublin, fol. 67a.