Therefore, prepare your minds for action;
I heard a pastor one time say that when you see the word therefore that you should look and see what it is there for. It sounds a little cheesy, and I try to avoid cheesy as much as possible, but this is a really good thing to remember.
If you go back before this therefore, you will see all of these amazing things that the Father has done through the Son, and we are reaping the benefits. Things that are so amazing that the angels are longing to look into these things. Because of all of this, there is a certain reaction that should take place in people when they realize these things. The next few verses describe how we should react.
This verse begins by telling us to prepare our minds for action. It is reminiscent of a battle scenario. The battle begins in the mind. This is a huge thought that I don't want to skim over. Don't miss its significance. Before you can defeat any temptation and begin to live the true Christian life, you must be prepared in your mind. There are way too many who have fallen because they thought that they could live righteously on the outside, and all the while they were acting out the worst imaginable sins on the inside. It just can't work. In the words of Jesus, "...first clean the inside of the dish, then the outside will be clean also."