In his book "Islam And The West," Bernard Lewis writes, "The primary duty of the Muslim as set forth not once but many times in the Quran is 'to command good and forbid evil.' It is not enough to do good and refrain from evil as a personal choice. It is incumbent upon Muslims also to command and forbid." Or as the Canadian columnist David Warren put it: "We take it for granted that it is wrong to kill someone for his religious beliefs. Whereas Islam holds it is wrong not to kill him."