What Is “Evil”? [Questions That Haunt]

This week’s Question That Haunts comes from Tanya:

I have a question about evil. Basically, what is it? When people say “evil” do they just mean really, really bad? The shootings in Sandy Hook are “evil,” passing a bad check is just bad. No? How does this work? Is this something where knowing the Greek or Hebrew words for “evil” will let you in on something?

Leave your answer below and I’ll proffer an answer on Friday.