The Khawarij (or Kharijites) were the first sect to emerge in Islamic history, splitting from the main body of Muslims during the caliphate of Ali bin Abi Talib (RA). They were known for their extreme and rigid views, particularly the belief that any Muslim who commits a major sin becomes a disbeliever (Takfir). They famously adopted the slogan "No judgment but God's." Their radical ideology led to widespread violence and internal strife. Though the original group disappeared, their "Takfiri" mindset has occasionally resurfaced in various extremist movements throughout history, which mainstream Islamic scholars have consistently denounced. The Khawarij emerged after the Battle of Siffin (657 CE). When Ali agreed to arbitration, a group of his followers objected, saying "No judgment but God's," meaning that human arbitration had no authority. They declared that Ali had become a disbeliever for accepting arbitration. They also declared that anyone who committed a major sin was a disbeliever, and they killed many Muslims whom they considered apostates. Ali fought them at the Battle of Nahrawan (658 CE), defeating them. However, the Khawarij ideology persisted. They believed in strict, literal interpretation, takfir (declaring others disbelievers), and rebellion against rulers they deemed unjust. The Prophet had predicted their emergence, saying: "A people will come who recite the Quran but it will not go beyond their throats; they will pass through Islam like an arrow through a target" (Bukhari). For believers, the Khawarij are a warning against extremism. They show the dangers of takfir (excommunicating others), of violence, and of abandoning the community. The believer follows the mainstream, avoids extremism, and respects the scholars who have preserved the tradition.