Ahmad Raza Khan Barelvi was a Sunni Islamic scholar and sufi, whose works influenced the Barelvi movement of South Asia. Raza Khan wrote on numerous topics, including law, religion, philosophy and the sciences. He was a prolific writer, producing nearly 1,000 works in his lifetime.

Ahmed Raza Khan was born on 14 June 1856 (1272 AH) in Bareilly, Uttar Pradesh, India; his mother named him Amman Miyan. Raza Khan used the appellation "Abdul Mustafa" (slave of Mustafa) prior to signing his name in correspondence. He studied Islamic sciences and completed a traditional dars-e nizami course under the supervision of his father Naqi Áli Khan, who was a legal scholar. He went on the Hajj with his father in 1878.

Ahmed Raza Khan promulgated several beliefs regarding the Islamic prophet Mohammed: 

. He is noor (light) as well as bashar (human), that is, noor-ul-bashar ("both light and human") 
. He is haazir naazir (present in many places at the same time, as opposed to God, who is everywhere by definition) 
. God has granted him ilm-e-ghaib (the knowledge of the unseen) 
. God has made him mukhtaar kul (having the authority to do whatever he desired)

Ahmed Raza Khan translated the Quran into Urdu, which was first published in 1912 under the title of Kanz ul-Iman fi Tarjuma al-Qur'an. The original manuscript is preserved in the library of Idara Tahqiqat-i-Imam Ahmed Raza, Karachi, and an English translation of Kanzul Iman has also been published. Ahmed Raza Khan also wrote several books on the collection and compilation of hadiths.

Raza Khan's main work was Fatawa Ridawiyya which runs in 12 volumes of over 1000 pages each. The Raza Foundation under the leadership of Abdul Qayyum Hazarwi revised the work, translating all the Persian and Arabic sentences in Urdu, and published it in 30 volumes, running across 90,000 pages.

Raza Khan investigated numerous religious questions: 

. In 1915 he wrote a treatise describing 160 types of water which are acceptable for wudu (ablution), and 146 types of proscribed water. 

. He identified 181 acceptable and 130 unacceptable materials for tayammum (alternatives to water for ablution). 
. He was able to fill up the Naqsh-i-Murabba (a sixteen column quadrilateral) by 1152 methods. 
. He knew 800 names of Muhammad from books, and was able to gather 1400 more. 
. He analysed whether it was credible that Hussain was able to travel from Mecca to Kerbala on 3rd Zilhij and reach there on 2nd of Moharram. He investigated the types of horses, the loads they carried, the route of the caravan, the types of terrain, and other factors, and finally concluded that the caravan could feasibly have reached Kerbala by the 2nd.

Raza Khan opposed the belief in a heliocentric universe, instead stating that the sun and moon circulate around the Earth.

Raza through his book published in 1912, presented four points for the economic development of Muslims: 
. Barring the affairs wherein government is involved, Muslims should decide all their disputes mutually so that millions of rupees, which are being spent over litigations, may be saved. 

. The affluent Muslims of Bombay (Mumbai), Calcutta, Rangoon, Madras and Hyderabad should open banks for other poor Muslims. 
. Muslims should not purchase anything from anybody except Muslims. 
. The sciences of Islam should be propagated and publicized.

Mirza Ghulam Ahmad of Qadian claimed to be the Mahdi (messiah) awaited by the Muslims. These claims proved to be extremely controversial among many in the Muslim community, and he was branded a heretic and apostate by many religious scholars of the time, including Ahmed Raza Khan. Ghulam Ahmad's claims are controversial to this day, but his Mahdi status is believed in by the Ahmadiyya branch of Islam.

When Ahmed Raza visited Mecca and Medina for pilgrimage in 1905, he prepared a draft document entitled Al Motamad Al Mustanad ("The Reliable Proofs") for presentation to the scholars of Mecca and Medina. Ahmed Raza Khan collected opinions of the ulama of Hejaz and compiled them in an Arabic language compendium with the title, Husam al Harmain ("The Sword of Two Sanctuaries"), a work containing 34 verdicts from 33 ulama (20 Meccan and 13 Medinese). The work concluded that Ghulam Ahmad's beliefs were blasphemous and tantamount to apostasy.

During the period of the Indian Khilafat Movement, Gandhi was advised that he should meet with Raza Khan. When he was told that the Gandhi wished to meet and speak to him, Raza Khan said, "What would he speak about? Religion or worldly affairs? If it is worldly affairs, what can I partake in, for I have abstained from the world and have no interest in it."

Raza Khan condemned many practices he saw as bid'at (forbidden innovations), such as: 
. Qawali (religious music) 
. Women going to mazaar 
. Tawaf (ceremonially walking in circles around a holy site) of tombs. 
. Sajda to ghair Allah 
. Tazia 

. He issued fatwas against other religious group such as Deobandis and Wahabbis, accusing them of being disrespectful towards the prophet Muhammad. Deobandi and wahabi scholars believe that AhmedRaza Khan has made these accusations due to his "exaggeration" in loving the prophet, which they claim violates hadith which proscribe deifying Mohammad. 
. He advocated the practice of asking to deceased Muslims, which his opponents declared to be shirk (polytheism):

If you are embarrassed in your affairs, seek help from the inmates of the tombs,having beliefs that Allah is the one who is helping and the person in the tomb is just wasila.

He declared that the sub-continent is Dar-ud-Dawah.and jihad against British is not obligatory,due their Ahlul kitab status.