We know the promise of God that He will always be with us and He will never leave or forsake us. We think we believe it because we have accepted it as truth. We even quote it and tell other people. But what happens when we are going through some dark times in our life? We can't see Him or observe His presence through His interventions. At such times, we may think God is not with us, perhaps He has left us or become angry with us because of something we have done or not done, etc. What we are doing then is choosing not to believe in Him, by ignoring His promises and trusting instead in our thoughts and feelings. Then we can't enjoy the comfort that comes from knowing that He is with us, that He is not only aware of our situation, but He is also in control. The fault is not God's at all, but entirely ours. We have become unbelieving believers!
It is what we choose from moment to moment that shows us whether we believe or not in real life. People tend to classify themselves as 'believers' based on the choice they made in the past. They hear of God's promises often. Then they wonder why many of His promises are not being fulfilled in their life. That is because when it comes to actual situations, they choose unconsciously not to believe in God's promises.
Imagine a situation where you feel alone, with nobody to help you. Nobody even understands your situation. The Holy Spirit reminds you that God understands, that He is with you. But you think, if God was indeed with you, you would not have been in that situation. Now you wonder where God has gone, why He is not there helping you as you expected. In your mind, it is all God's fault. You wonder how He can be trusted. You think you will have to take care of yourself.
On the contrary, when a difficult situation begins to put pressure on you, you can remind yourself God is with you, and He will not leave you. As your heavenly Father and Friend, He will certainly not 'ditch' you especially when you are in trouble. He has sent Jesus to save you and not to judge you. When you begin to hold on to God like this, you will find that the 'pressure' has come down. Your situation may not have changed, but now you begin to feel confident that you are safe in the Father's hands, and that He will take you through.
Now you can understand why God says that victory comes through faith (1Jn.5:4). This faith is our trust in God through Jesus. God has given us His word so that as we apply it to us in the different situations of life and obey Him, we can enjoy victory. It must be clear by now that our faith that we expressed in Jesus when we came to Him at first must be applied moment by moment for us to live in victory. One common mistake is to think that we have put our faith in Jesus on a certain day, and afterwards it is His responsibility to take care of us. Then we can understand why we feel like blaming Him when things go wrong. No. If we have faith, we must also walk by that faith.