:rolleyes: when someone has been raped or murdered are we not to say or do anything? People say that certain things are to happen to people but we don`t expect the bad ones.

It's can be expressed quite simply. Either something is right or it is wrong. But since this simple rule is hardly ever followed completely the next best thing is man made justice. To take retribution into your own hands is not justice, it is revenge. And revenge is wrong.
As to whom is the victum and who is the perpetrator the answer to that is we are both at some time or another.