Spirituaity is Islam 

 

"Sufism and Islam cannot be separated in the same way that higher consciousness or awakening cannot be separated from Islam. Islam is not an historical phenomenon that began 1,400 years ago. It is the timeless art of awakening by means of submission. Sufism is the heart of Islam. It is as ancient as the rise of human consciousness."

The following quotations of the Scholars of Shariat regarding the precedence of the knowledge and science of Sufism-Tasawwuf (Purification of the Self):

Imam Abu Hanifa (85 H. – 150 H.)
“If it were not for two years, I would have perished.” He said, “for two years I accompanied Sayyidina Ja’far as-Sadiq and I acquired the spiritual knowledge that made me a gnostic in the Way.” 
[Ad-Durr al-Mukhtar, vol 1. p. 43]

Imam Malik (95 H. – 179 H.)
“whoever studies Jurisprudence [tafaqaha] and didn't study Sufism [tasawwaf] will be corrupted; and whoever studied Sufism and didn't study Jurisprudence will become a heretic; and whoever combined both will reach the Truth.” 
['Ali al-Adawi , vol. 2, p 195.]

Imam Shafi’i (150 – 205 AH.)
“I accompanied the Sufi people and I received from them three knowledges: …how to speak; how to treat people with leniency and a soft heart… and they… guided me in the ways of Sufism.”
[Kashf al-Khafa, 'Ajluni, vol. 1, p 341.]

Imam Ahmad bin Hanbal (164 – 241 AH.)
“O my son, you have to sit with the People of Sufism, because they are like a fountain of knowledge and they keep the Remembrance of Allah in their hearts. they are the ascetics and they have the most spiritual power.”
[Tanwir al-Qulub p. 405]

Imam Ghazzali (450 – 505 AH.)
“I knew verily that Sufis are the seekers in Allah’s Way, and their conduct is the best conduct, and their way is the best way, and their manners are the most sanctified. They have cleaned their hearts from other than Allah and they have made them as pathways for rivers to run receiving knowledge of the Divine Presence.”
[al-Munqidh, p. 131].

Fakhr ad-Din ar-Razi (544 – 606 AH.)
“The way of Sufis for seeking Knowledge, is to disconnect themselves from this worldly life, and they keep themselves constantly busy with Dhikrullah, in all their actions and behaviors.” 
['Itiqadaat Furaq al-Muslimeen, p. 72, 73]

Imam Nawawi (620 – 676 AH.)
“The specifications of the Way of the Sufis are … to keep the Presence of Allah in your heart in public and in private; to follow the Sunnah of the Prophet (s) … to be happy with what Allah gave you…”
[in his Letters, (Maqasid at-tawhid), p. 20]

Ibn Taymiyya (661 – 728 AH.)
“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].
“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 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]. 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 Khaldun (733 – 808 AH.)
“The way of the Sufis is the way of the Salaf, the preceding Scholars between the Sahaba and Tabi’een of those who followed good guidance…”
[Muqaddimat ibn al-Khaldun, p. 328]

Tajuddin as-Subki (727 – 771 AH.)
“May Allah praise them [the Sufis] and greet them and may Allah cause us to be with them in Paradise. Too many things have been said about them and too many ignorant people have said things which are not related to them. And the truth is that those people left the world and were busy with worship. …They are the People of Allah, whose supplications and prayer Allah accepts and by means of whom Allah supports human beings”
[Mu'eed an-Na'am p. 190, the chapter entitled Tasawwuf]

Jalaluddin as-Suyuti (849 – 911 AH.)
“At-Tasawwuf in itself is the best and most honorable knowledge. It explains how to follow the Sunnah of the Prophet (s) and to put aside innovation.” [Ta'yid al-Haqiqat al-'Aliyya,p 57]

Ibn Qayyim (691 – 751 AH.)
“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.]

Shah Abdul Haqq Dehlawi (958 – 1052 AH.)
“Hearken that the foundation of the Faith and its consummation rest on fiqh, scholastic philosophy (Aqeedah) and Sufism (Tasawwuf)”. [Al-Lam’at-Sharah-Mishkat, p 45]

Shah Waliullah Muhaddith Dehlwi (1115 – 1176 AH.)
“The spiritual successor of the Prophet will be the person who has acquired all the three aspects of religion as illustrated in Hadith-e-Gabriel, is well versed in the Book and the Sunnah and endeavors in the canons of mystic knowledge and guidance of its seekers”. [Tafhimat-e-Ilahiya P 13]

Abdullah ibn Muhammad ibn Abdul Wahhab (1115 – 1201 AH.)
“My father Muhammad ibn Abdul Wahhab and I do not deny or criticize the science of Sufism, but on the contrary we support it, because it purifies the external and the internal of the hidden sins, which are related to the heart and to the outward form. Even though the individual might externally be on the right way, internally he might be on the wrong way. Sufism is necessary to correct it.” 
[ad-Dia'at mukathaffa did ash-shaykh ibn Abdul Wahhab, p. 85]

Qazi Thanaullah Panipati (d. 1225 AH.)
“The attainment of knowledge termed as ‘Ilm e ladunni (Knowledge of His Presence) by the Sufis is obligatory, for its fruits are cleansing of the heart from wayward impulses and its absorption in perpetual observation. Purification of soul from moral ailments like arrogance, conceit, jealousy, love for wealth and status, weariness in Divine worship, sensuality, cant, etcetera and in their place attainment of high moral virtues e.g. conversion, acquiescence to the will of Allah, gratitude, fortitude etc. is the essential. There is no doubt that the said moral ailments are, for a believer, deadlier that the sins he commits with his physical body while the virtues listed above are of a greater significance that Salaah, fasting and Zakat because any kind of worship devoid of sincerity is of no consequence. And it is this sincerity which is the other name of Sufism.” 
[Tafsir-e-Mazhari Vol. 4 P 324]

Ibn ‘Abidin (1198 – 1252 AH.)
“The Seekers in this Sufi Way don’t hear except from the Divine Presence and they don't love any but Him. If they remember Him they cry, and if they thank Him they are happy; … May Allah bless them.” 
[Risa'il Ibn 'Abidin p. 172 & 173]

Muhammad ‘Abduh (1265 – 1323 AH.)
“Tasawwuf appeared in the first century of Islam and it received a tremendous honor. It purified the self and straightened the conduct and gave knowledge to people from the Wisdom and Secrets of the Divine Presence.”
[Majallat al-Muslim, 6th ed. 1378 H, p. 24].

Maulana Abul Hasan ‘Ali an-Nadawi (1331 AH.)
“These Sufis were initiating people on Oneness and sincerity in following the Sunnah of the Prophet (s) and to repent from their sins and to be away from every disobedience of Allah ‘Azza wa Jall. Their guides were encouraging them to move in the way of perfect Love to Allah ‘Azza wa Jall.

May Allah seize all your worries, hardships, diseases and scatter eternal Peace, Love and Happiness by the sake of the Beloved Prophet Muhammad (Peace be upon him) Aameen.