[1] He was the mentor of Mullah Mohammed Omar, and his madrassa (known as Banuri Town), "taught many students who later became important members of the Taliban regime in Kabul".
[1] He issued religious edicts and travelled to elicit support for the Taliban, including a called for a “jihad” against the US after the Al-Qaeda September 11 attacks and US invasions of Afghanistan and Iraq.
[1] His funeral prayer was led by Abdur Razzaq Iskander, and was attended by Akram Khan Durrani, former Chief Minister of Khyber Pakhtunkhwa, and Fazal-ur-Rehman, President of Jamiat Ulema-e-Islam (F).
Shamzai and his fatwa were, according to Zahid, "instrumental in galvanising anti-American protest movements in Pakistan after the 9/11" against the U.S. intervention in Afghanistan in 2001 and in the thousands of Pakistanis who later "joined the Afghan Taliban".
"[9] In preaching theKul-eBandigi (devout following of Islam) concept, Shamzai emphasises Kasur, i.e. the mistake committed by too many in the Muslim community (ummah) of not participating in violent jihad in Afghanistan, Kashmir, Chechnya, Burma and elsewhere.
[13][14] He "promoted the Afghan Taliban regime, their religious practices, enforcement of Sharia laws, treatment of women and minorities and legtimised their actions through his fatwas".
Representative of his feelings was a fatwa issued in 1998 (at the forum of Majlis-eTaawun Islami Pakistan i.e. Organisation for Islamic Cooperation, of which he was Emir and founder)[9] “If Sheikh Osama is Captured or Harmed, Jihad will Become Obligatory Against all Governments Involved in the Operation”[9] Shamzai "preached systematic anti-Semitism ... weaved within conspiracy theories" and is credited with being a major contributor to the growth of anti-Semitism in Pakistan by Zahid.
[9] In addition to hating Jews he also despised the anti-jihadi media as expressed in one statement: “Dawn the newspaper from Karachi, and others like The Frontier Post, The News International and other newspapers published in the country, are all part of Jewish media's conspiracy against Islam, jihad and madrassas.”[9] Apart from contributing a weekly religious column to a daily, he wrote in several Islamic journal as well many books, including Zahoor-i-Imam Mehdi and exegeses of Sahih Bukhari and Jami` at-Tirmidhi.