James 1:23-24 For if anyone is a hearer of the word and not a doer, he is like a man observing his natural face in a mirror; For he observes himself and goes away and immediately he forgets what kind of man he was.
As Christians, we must always remember who we are in Christ. We must hear the Word of God, heed the Word of God, and then meditate on it at home after we leave church.
Sometimes we just don't think about it. We may go to church and say, "Well, that's what God's Word says. I know that." Then we go out and forget all about it. We don't line our lives up with the Word we just heard preached. Sometimes we come to the place where we get too dependent on God's grace and mercy. But we should not depend on God bailing us out of situations we know we can grow out of by remembering and meditating on and applying His Word.
We are commanded to be strong and courageous. But nobody starts out that way. A young man entering the army may go in afraid and make lots of mistakes. He may be that way on day one, but he'll not stay that way if he follows the commands of the drill sergeant, believe me I know from experience. Even though we have received Jesus and we may still make some mistakes, it does not mean that we will stay that way. When we stick with the Word and get to know and remember Jesus' nature and character, we will also get to know our heavenly Father, and we will begin to learn how to stand strong and win on the battlefield.
As the victories come we remember that God is on our side, helping us win each battle. Then, when another battle comes we already know what the outcome will be. We will win that one just like we won the others. We have to remember God said He would protect us and He does what He says. God said in Isaiah 54:17 "No weapon formed against you shall prosper." That is because He is our protection if we remember to do the things He told us to do.
We must remember what God said at the time of the attack. The way to do that is to continue to meditate on what He has said all day long, especially during peacetime - the time when there are no attacks. Then, when an attack comes, we will remember what God said. We will remember exactly who we are; soldiers on God's winning team led by our commanding officer.