According to Juergensmeyer, religion and violence have had a symbiotic relationship since before the Crusades and even since before the Bible. He defines religious terrorism as consisting of acts that terrify, the definition of which is provided by the witnesses – the ones terrified – and not by the party committing the act; accompanied by either a religious motivation, justification, organization, or world view.:4–10 Religion is sometimes used in combination with other factors, and sometimes as the primary motivation. Religious terrorism is intimately connected to current forces of geopolitics.
Bruce Hoffman has characterized modern religious terrorism as having three traits:
- The perpetrators must use religious scriptures to justify or explain their violent acts or to gain recruits.
- Clerical figures must be involved in leadership roles.:90
- Perpetrators use apocalyptic images of destruction to justify the acts.:19–20