Fighting evil! I love Lord of the Rings and the Hobbit for these ideas.
(This has spoilers for the Hobbit)
One of my all time favorite quotes is from Gandalf, below.
“I wish it need not have happened in my time," said Frodo.
"So do I," said Gandalf, "and so do all who live to see such times. But that is not for them to decide. All we have to decide is what to do with the time that is given us.”
Fellowship of the Ring