Considering the evil of the schism produced by the Takfiri murders and in view of the efforts of Kharijites under Imam Ali’s government to commit such murders, it is necessary to answer the following questions: “What did Imam Ali say in encountering the Takfiri murders committed by Kharijites, and are his sayings applicable for the present era?” To find the answers, the present article, first, refers to Nahj al-Balagha and the historical authentic books to gather Imam Ali’s sayings about Kharijites from their first Takfiri murder up to the end of Nahrawān Battle. Then, using a consistent method and the ‘thematic content analysis’, it has separated the most important primary and secondary sayings. The result of this effort was finding 10 sermons, dialogues and letters that can be divided into 4 general themes. 70% of those contents denote Imam Ali’s efforts to negate Kharijites’ Takfiri accusations on himself, familiarizing them with the seditionist characteristics of Kharijites and their associates. In view of the materials in this section, it is quite possible that Kharijites were not, in their motivations and religious sincerity, examples of today’s Takfiri groups. The rest 30% of the contents denote Imam Ali’s efforts to make Kharijites examples for others to take lessons from, restricting toleration with Kharijites, and making them understand the fact that the origin of their Takfiri accusations on Imam was their own wrongdoings, not that of Imam, although some of Imam Ali’s tolerations with Kharijites may not be suitable for the present era.