Freezer if you were a juror would you give someone life for burning down someones property? what the property was should have no correlation to jailtime, For the sake that they were all churches they should bring a psychologist into the case, not just have a jury of probably god fearing folk sentence the people. They have obvious mental disorders they the jury themselves dont know anything about.
Forget religion, forget the hundreds that could've been killed, forget the fires we don't know about. Do serial crimes, do serial time.
Life = 40 to 60 years. Divide by 10 fires... 4 years isn't cruel or unusual, if anything it's light.