You might explain to your children that history is often biased by the teller. Other discussion topics:
- some of the ways that the Crusades involved some impure motives as well as pure
- Pope Urban promising a "free ticket to heaven" (as the video discusses) for anyone who promised their soul to the Crusades. Can a Pope do that? How does the Bible say we're saved in verses like Ephesians 2:8-9? What might have prevented Christians from knowing verses about grace (i.e. not having a Bible in the language they spoke)?
- What do they think about the Crusades? Were they a wise idea? Why, or why not? How do they think that the Bible suggests we respond to actions like the Muslim occupancy of Jerusalem?
- Verses to consider: Luke 17:20-21; 1 Peter 3:15-16; Colossians 4:5.
- For older children, discuss the difference between the Israelites taking over the Promised Land in the book of Joshua versus modern-day religious aggression, like the recent Quran-burning day. I gently suggest the difference between Old Testament responses to other religions and New Testament responses were that in the Old Testament, God was creating a pure nation--a pure people--holy to Himself. Now, He's still concerned about a pure people, but those people are His Church: us.
- Do we ever do things with mixed motives? What can happen when mixed motives lead a lot of people? Verses to consider: Matthew 5:8; Psalm 86:11; Ezekiel 11:19.
- Can good things happen from impure motives? Can bad things ever happen from pure motives?
- When might military action against another religion be a good thing? (An example: preventing the spread of Islam through the Battle of Tours; the battle of Armageddon.) How can we tell the difference? How is our world and our country different from those who went to fight against Islam?