**When Christians say "Jesus died for our sins", what do they mean?**

      I went to Catholic school for 5 years and all I heard was "Jesus died for our sins", "Jesus sacrificed himself for us!!", and "Jesus was the Messiah!". What do you mean by this?
As far as I'm concerned, everyone still "sins" all the time.

      Which brings me to my next point...

      Why call Jesus a messiah? Was it impossible to be a good person before he "sacrificed himself for us"?

      This isn't meant to be a hostile question... I really want to know what you mean when you say this kind of stuff.