Explain Like I'm Five

My general understanding is that you're forgiven if you choose to accept Jesus. (Note that I am not christian, but was raised as such.) You are not required to accept salvation. Actions, by themselves, mean nothing; you can be a fantastic, moral person, and work all of your life to help other people, and without accepting Jesus you're still damned. OTOH, if you have truly accepted Jesus, then ipso facto you're going to work tirelessly to help people; actions are a natural consequence of the belief. Therefore, someone that acts contrary to the teaching of Jesus is not saved, because they do not have true belief.

For a real world example, Jimmy Carter would be a person that you could say would be saved (...if any of this was real); his effort demonstrates the faith he claims. OTOH, looking at all of the televangelists, you could quite reasonably say that their daily lives contradict the teachings of Jesus, and therefore no professed belief can ever result in their salvation.