Choosing the Right Shield

The other night I was out with friends from work, some of them are not LDS which leads to some pretty awesome or awkward conversations.  We were laughing about how some of us are immature while others are more responsible. 
Let's guess who fell into these rolls ;)
Pause
Remember back in primary when we were given CTR rings with that little green shield encircling those letters?  I never understood how a little ring with three letters could 'protect' me.  I knew that if I followed those little words that I would be blessed but never did I think that a ring could actually protect me from outside forces.
Resume
While laughing at a mildly inappropriate joke I shook my head at my friend, teasing him about his foul mouth when he said, "Trust me.  If it wasn't for your little ring there I would've said and done a whole lot worse."  I asked him what MY ring had to do with his language and/or behavior.  All he could do was shake his head and say 'I don't know'.
I've noticed for myself while having side conversations with friends saying that he is different around me, that he tries to be a better man.  Or there are times that he goes to say something but chokes on his own words.  It's like there is something thing pushing him to be a little better.
For the first time in my life I realized that because of a simple little choice I make on a daily basis to show my faith that it could literally protect me from outside forces.  My friend doesn't really understand what he is feeling, but he has mentioned in several conversations that he knew from the first moment we met that he couldn't mess with me, couldn't hurt me, and that I was a force to be reckoned with, simply because I wore a ctr ring.
I guess choosing a shield to carry every day doesn't have to be a large and heavy one.  A simple little band can do wonders.