He was previously the president of the Pakistan Democratic Movement (PDM), a coalition of political parties which ousted then prime minister Imran Khan through a no-confidence motion in 2022.

[10] After defeat in the 2018 Pakistani general election, Rehman was ejected from the National Assembly and failed to win major political support in Khyber Pakhtunkhwa, bagging only 10 of the 99 seats in his home turf.

[12] Rehman was born on 19 June 1953[13] (1 September according to another report) to a Marwat Pashtun family,[14] in the village of Abul Kheel in Dera Ismail Khan.

[15][16] His father, Mufti Mahmud, was an Islamic scholar of the Deobandi branch and a politician who served as the Chief Minister of Khyber Pakhtunkhwa from 1972 to 1973.

[5] His early education was from Millat High School, Multan and was a student of Mussarat Baig and Syed Iqbal Shah.

During his early religious training and education (Ilm Us Saraf, Ilm Un Nahv, Logic) he remained the disciple of Mufti Muhammad Essa Gurmani and Molana Abdul Ghaffor Gurmani of Shadan Lund before studying Sharah-e-Mata-e-Aamil and Hidayat-un-Nahv with Muhammad Ameer of Chudwan in a Madrassa at Jhok wains Multan .

[17] He was a student of Abdul Haq Akorwi, Hasan Jan, and Syed Sher Ali Shah during his Shahadat-ul Alamia at Darul Uloom Haqqania.

[20] Rehman led several anti-American protests and pro-Taliban rallies in the major cities of Pakistan following the war in Afghanistan in 2001.

[22] Rehman ran for the seat of the National Assembly of Pakistan in 2008 Pakistani general elections for the sixth time on Muttahida Majlis-e-Amal ticket from two constituencies, NA-24, D.I.

[28] Rehman ran for the seat of the National Assembly of Pakistan in 2018 Pakistani general elections from Dera Ismail Khan's constituencies, NA38 and NA 39 but did not win.

[34] On numerous occasions, Rehman has displayed severe opposition to Imran Khan and his political party, the Pakistan Tehreek-e-Insaaf (PTI).

In 2013 Rehman declared voting for the PTI as haram (religiously prohibited), asserting Khan to be supported by the West and the Jewish lobby and explicitly calling him an agent of "Americans, Jews, Ahmadis and a person of ill character".

[41] Mufti Abrar, the party's spokesperson, stated that on 31 December 2023 the politician's convoy was fired upon from multiple sides at Yarik interchange in Dera Ismail Khan, Fazl's home city.

President of the Pakistan Muslim League-Nawaz (PML-N), Shehbaz Sharif, responded to the incident by denouncing the attack on Fazl's convoy and expressing relief over the politician's safety.

[45] On 5 December during a press appearance in Islamabad, the politician commented: "There is no police in Dera Ismail Khan, Tank, and Lakki Marwat.