It is therefore enjoined upon every Muslim to wage a regular crusade against all innovations.
Source, in full
Quoted and attributed in Saiyid Athar Abbas Rizvi, Muslim Revivalist Movements in Northern India in the Sixteenth and Seventeenth Centuries, (New Delhi: Munshiram Manoharlal Publishers Pvt. Ltd. 1965), 256, quoted from Ibn, Warraq (2017). The Islam in Islamic terrorism: The importance of beliefs, ideas, and ideology. ch 15