This short essay will briefly cover the Ahmadiyya takfeer policy and its correlation with extremism in the Ahmadiyya movement. It should be noted that the split in the Ahmadiyya Movement which happened in 1914 was based on two opposing ideologies in terms of Takfeer, here is a neutral account of the differences in the two branches of Ahmadiyya:
“For some time, there had been two parties in this Movement over the question of takfir. One party believed that non-Ahmadis are Muslims even though they may not believe in Mirza sahib’s claims. The other party, however, declared openly and clearly that those people who do not believe in Mirza sahib are kafir absolutely — inna li-llahi wa inna ilai-hi raji‘un. The head of the latter party is Mirza Bashir-ud-Din Mahmud Ahmad, and this faction has now made him khalifa but the first group does not accept this. The writing published in this connection by Maulana Muhammad Ali, and the wonderful and admirable courage he has shown in expressing these views while staying in Qadian, where the heads of the other party live, is truly an event which shall always be regarded as a memorable event of this year.” (See Al-Hilal, dated 25 March 1914, edited by Maulana Abul Kalam Azad) (Also See “A Mighty Striving” by Mumtaz Ahmad Faruqi, page 111, online edition).
Factually, the debate of Takfeer in terms of Ahmadiyya had started as early 1891, as soon as MGA laid claim to being “the messiah” (1891), after consultation, the ulema of India declared MGA to be a Kafir, since MGA was hinting towards a claim of prophethood in his writings. However, MGA refused to accept this religious opinion (fatwa) and offered explanations in terms of his claim to prophethood, he claimed that the ulema was lying, he claimed that his prophethood was only metaphoric and thus the ulema had simply misunderstood his claim. He continued to deny any and all claims to prophethood in over 30 books that were published from 1891 to 1901.
In fact, in 1899, while writing Tiryaq ul Qulub (which was eventually published in 1902), MGA wrote that his deniers were not Kafirs, and since his claim wasnt that of prophethood. In fact, in that same year, he was ordered by the British Govt. to never call any of his deniers as Kafirs.
However, in Nov of 1901, he discovered a new definition of prophethood, and thus claimed prophethood officially, and thus proved the ulema of India as correct in their assumptions. However, he didnt come out and call his deniers as Kafirs per the Quran.
In 1904, MGA starting using a hadith wherein anyone who called a Muslim a Kafir was himself a Kafir, this was how MGA’s policy in terms of Takfeer was evolving. However, he still hadnt dealt with his claim of prophethood and its implications on the Muslims of the world.
In the 1906-1907 era, MGA began writing about his deniers as a second class of Kafirs.