Takfir
In his widely influential book , "Milestones" , Islamist theorist Sayyid Qutb preached that "all" of the Muslim world had become apostate or "jahiliyah" ( a state of pre-Islamic ignorance ) , centuries ago , having abandoned the use of sharia law , without which ( Qutb held ) Islam cannot exist . 
<triplet> Milestones <subj> Sayyid Qutb <obj> author