Fanaticism is divided into two categories:

1. Fanaticism towards personalities: for example, the Christians towards ʿĪsāʾ ibn Maryam. Likewise, the fanaticism of the Shīʿah towards ʿAlī ibn Abī Ṭālib and his descendants, etc.
2. Fanaticism towards ideologies: this is more dangerous than the previous type of fanaticism because fanaticism towards personalities only destroys the fanatic, but fanaticism towards ideologies destroys the religion, societies, countries, and nations — it destroys everything. This is like the fanaticism of the corrupt Khawārij terrorists; if their ideology is found with a people then they become corrupt because they cause corruption and claim rectification. They ruin whilst claiming to be gaining closeness to Allāh, killing innocent souls and spilling sacred blood, all the while claiming “jihād” in the path of Allāh.

Source: Risālat al-Gulū Ḍamn al-Rasāʾil al-Manhajiyyah.
Translated by: Munīb al-Ṣumālī