"You can't be right by doing wrong;

You can't be wrong by doing right"

Thomas S. Monson

You can't be right when you're doing something that is wrong to do.

You can't be wrong for doing something you know that is the right thing 

to do. What Thomas S. Monson is saying in this quote is that if you do wrong it can't be right and if you do right it can't be wrong. It works this way because if your doing something that is right, 

how can it be wrong? This is a reminder to do right because its the right thing

 to do. When you do what is right you feel good because its right and it can't be wrong. Doing the right thing is very simple as long as you don't think about doing the wrong.