Simplify the following text for a Grade 11 native English-speaking person.
Original: Christians believe the resurrection of Jesus to be the main part of their faith ( see 1 Corinthians 15 ) and the most important event in human history , because it would show that Jesus has power over death and has the authority to give people eternal life .
Simplified: Christians consider the resurrection of Jesus to be the cornerstone of their faith ( see 1 Corinthians 15 ) and the most important event in human history .