The Ruling on Fighting the Khawarij

Question:
The Khawarij declare people to be disbelievers; they declare sinners to be disbelievers. The Khawarij are the ones who started this. They go out with the people and say, "The fornicator is a disbeliever, and the thief is a disbeliever." The Prophet (peace and blessings be upon him) said, "If you meet them, kill them." And there is nothing sweeter than going out [to fight them].

Answer:
The majority of scholars hold that they should not be fought, but rather that it should be made clear to them that they have erred and gone astray. However, the apparent meaning of the texts is that they are to be fought; that is, if they persist in their position and do not repent, they are to be fought, if Allah wills. The Shaykh is the one who phrases it thus: every one who goes out against a ruler is called a Khariji. No, the one who goes out is like the rest; and those who are abundant in sins are the Khawariji. Yes.