Relying on our Shield

Genesis 15:1
"After these things the word of the Lord came unto Abram in a ^avision, saying, ^bFear not, Abram: I am thy ^cshield, and thy exceeding great reward."

I know that this is something specific to Abram, but the blessing that is being said here does apply to us, if we let it. Christ is our shield, but from what? 

Well, you can't make an argument about how he protects us from physical harm all the time. He can and he does for the most part, but sometimes bad things happen to good people and they get hurt when they were at no fault. The same goes for intellectually. I have known or heard first hand stories of several people that were good people and because of one reason or another they lost their intellectual faculties. 

So, he is our shield from spiritual dangers. That is what is left in my mind. Someone may think of something different, but Christ is our shield from sin. We have to let Him be our shield, just like a soldier will have to chose to put on his or her armor for it to be effective, but once Christ is our shield, man is He effective.

Now, naturally, like a shield, He doesn't keep sin from coming at us. Sometimes it can be a blow that knocks us backward, but we can still resist it with His help.