Faith is the substance of things hoped for and the evidence of things not seen. Without faith it is impossible to please God. Even the salvation of our soul would not have been possible without faith (Ephesians 2:8-9); remember that the just shall leave by faith (Romans 1:1-17, Galatians 3:11). Faith is vital in our walk with God.
However, your faith could be weak, and as a result, you will not be able to receive what has been made available to us. Someone has rightfully said that faith is the currency that enables us to draw things from the spirit realm to this physical realm. Oftentimes the heat of the battle that we encounter can weaken our faith and cause us to be fearful. Notice the reactions of the disciples in Mark 4:35-41 when the storm suddenly arose. Jesus asked them why they were so fearful and without faith.
These were the disciples, the people who had first-hand experience of Jesus. They had seen Him perform many miracles, yet when the storm came their hearts melted. This shows that you do not build your faith in one moment. You must keep working at it. You must build your faith daily through the word. You must meditate on the word and speak the word to yourself over and over again.
You must therefore keep energising your faith in preparation of any battle to come. Our text says that by acknowledging that every good thing within us is also in Christ Jesus we make our faith effectual. There may be bad things that have happened or that are happening, but you should ignore them, open your mouth, and declare boldly the good things in you. “I am strong in the Lord”, “I am more than a conqueror”, “I can do all things”, etc. When you do so, spiritual energy will kick in and your faith will be strengthened.