The earliest Sufi Order was founded by Shaikh Abdul Qadir Jilani (may Allah be pleased with him) who died 1166 C.E. in Baghdad, Iraq. The Sufis of the Qadiriyah Order laid great stress on the purification of the self. According to this philosophy, purification of the mirror of the heart from rust of the carnal, animal and satanic qualities is the essential part of one's spiritual journey. The Sufis maintained that the human soul came from the world of command and is capable of reflecting the Divine Light, but due to impurities of the self, it does not do so.
If a mirror becomes rusty it cannot reflect any form placed before it, but when the rust is removed, it begins to reflect clearly. Thus if the mirror of the heart is clean, the beauty of the Beloved (Allah) reflects in it and one can see this in the personality of the seeker, inwardly and outwardly.
The Qadiriyah School of Mysticism is based entirely upon the principles of Shariah. In this School, the disciple (murid) accepts Shaikh Sayyiduna Abdul Qadir Jilani (may Allah be pleased with him) as his Grand Shaikh, testifying that the ahd (bayt, i.e. swearing allegaince by the hand) he is taking is the ahd of Almighty Allah and His Apostle (Allah bless him and give him peace) and that the hand of the Sufi Shaikh is that of Shaikh Sayyiduna Abdul Qadir Jilani (may Allah be pleased with him), and is expected to subordinate his will to his Spiritual Guide (Pir-i-Murshid).
Hazrat Ghaus-e-Azam (may Allah be well pleased with him) is a 'Najeeb-ut-Tarfayn' Sayyid, that is, his father traces his lineage to Imam Hasan (may Allah be well pleaded with him) and his mother traces he lineage to Imam Husayn (may Allah be well pleaded with him).
The venerable Muhyiddin Abdul Qadir al-Jilani, may his soul be sanctified, is al-ghawth al-azam [the manifestaion of Allah's attribute 'the All-Powerful'], who hears the cry for help and saves the ones in need, and al-qutb al-azam - the pole, the center, the summit of spiritual evolution, the spiritual ruler of the world, the source of wisdom, container of all knowledge, the example of faith in Islam; a true inheritor of the perfection of the Prophet Mustafa; a perfect man; and the founder of the Qadiriyah, the mystical order that has spread far and wide and preserved the true meaning of Islamic Sufism throughout these centuries until our time.
Even the famous 18th century theologian Shah Wali Allah [d.1762] of Delhi, whose primary Sufi affiliation is the Naqshbandi-Mujaddidiyya, praises and respects Abdul Qadir Jilani to such a great extent and declares that the most complete Sufi [in terms of having a connection to the Prophet] is Hazrat Shaikh Sayyiduna Shah Abdul Qadir Jilani (may Allah be well pleased with him). Therefore it is said that the spiritual power (tasarruf) at his blessed tomb is as if he were alive.
Shah Wali Allah further comments that the Qadiriya is near the Uwaisiyya [Uwaysi] and other paths involving disembodied spirits. There is nothing to compare to the Qadiriya when one learns from an embodied Pir with a connection and access to the spiritual energy of disembodied Pirs benefiting the aspirant. The deceased Shaikh Abdul Qadir Jilani is among the highest angels (al-mala al-ala) and he leaves an impression existence, which is felt, throughout the entire world. It is this, from the aspect of the soul (ruh) that one acquires in his spiritual path. Sayyiduna Abdul Qadir has a divine connection, meaning that he is desired by Almighty Allah (murad) and absolutely loved by Almighty Allah [Invincible and Exalted is He] . making him one of the perfected souls and one of the highest angels. This is why Hazrat Ghaus-ul-Azam [Ghawth-i Azam] is praised to such a high degree. Islam tell us that after death the soul lives in the Alam-i-Arwah [the soul world] which is also known as the Barzakh or the buffer-zone lying between this world and the next.
Clearly the Indo-Muslim elite, both Qadiri and non-Qadiri accorded a very high status to Shaikh Sayyiduna Shah Abdul Qadir Jilani (may Allah be well pleased with him) from the 15th century. [Source: The Indo-Pak Qadiriyya, Prof. Authur Buehler (Harvard University) from the 'Journal of the History of Sufism', Special Issue, the Qadiriyya Order]
May Almighty Allah [Exalted is He] be pleased with the Cardinal Pole [Qutb], the Spiritual Helper [Ghauwth], Muhyiddin Shaikh Abdul Qadir Jilani and may He sanctify the innermost beings of all His saints and servants. May Almighty Allah bless our beloved Master, the beloved Prophet Muhammad (Allah bless him and give him peace), his family, and his Companions, and may He grant them peace. Praise be to Almighty Allah [Exalted is He], the Lord of All the Worlds