If we want to start seeing the power of God manifest in our lives, we will have to start paying attention to what we say. Words have power—more than any of us realize, but we often speak them as though they are meaningless. Because of that, most believers at one time or another have been hung by their tongue.
Matthew 12:36-37 says,
“And I tell you this, you must give an account on judgment day for every idle word you speak.
 The words you say will either acquit you or condemn you.”
“Every idle word” simply means non-productive. These are words that we speak but don’t believe. For example, you might say, “I’m dying to see my grandchildren.” You really don’t mean you’re dying, but you say it anyway to emphasize the importance of the relationship.
Every time you say things that you don’t really mean, it begins to numb your heart. Unconsciously, each idle word is making it just a little bit harder to believe what you say will actually come to pass when you mean it and it really counts.
Jesus certainly understood the power of words, and He used them to change the natural things around him.
Mark 11:13-14 and 20-24 say,
He noticed a fig tree in full leaf a little way off, so he went over to see if he could find any figs. But there were only leaves because it was too early in the season for fruit.
 Then Jesus said to the tree, “May no one ever eat your fruit again!” And the disciples heard him say it.
 The next morning as they passed by the fig tree he had cursed, the disciples noticed it had withered from the roots up.
 Peter remembered what Jesus had said to the tree on the previous day and exclaimed, “Look, Rabbi! The fig tree you cursed has withered and died!”
 Then Jesus said to the disciples, “Have faith in God.
 I tell you the truth, you can say to this mountain, ‘May you be lifted up and thrown into the sea,’ and it will happen. But you must really believe it will happen and have no doubt in your heart.
 I tell you, you can pray for anything, and if you believe that you’ve received it, it will be yours.
I can almost hear the inflections in Peter’s voice when he said, “The fig tree You cursed is withered away.” I am sure it communicated surprise and disbelief of the Nation Israel in Lord Jesus Christ and thus cursed upon the fig tree. And when Jesus replied to Peter, it probably was not in a monotone voice. It was more like, “PETER! WHAT’S WRONG WITH YOU?” Jesus was amazed at his unbelief. He was saying, “It shouldn’t shock you to see this tree withered. Have faith in God.”
Then He went on to explain that this wasn’t limited to a fig tree. He used a mountain as an example, but I believe it could apply to anything. He was making the point that if we say it with our mouths and believe it in our hearts, we can have what we say.
He also made it very clear who qualified to use words in this way: He said, “whosoever shall say.” Are you a whosoever? Because if you are and if you’re breathing, then you’re qualified, and your words can affect the natural as well as the spiritual world.
Jesus used the word “say” or “saith” in verse 23. He was making it clear that words have power. But He also said to have faith in God. The words that have power are words that are filled with faith. And it’s important to understand that the faith they’re filled with is not your human faith.
Galatians 2:20 says,
“My old self has been crucified with Christ. It is no longer I who live, but Christ lives in me. So I live in this earthly body by trusting in the Son of God, who loved me and gave himself for me.”
If we can’t even believe for salvation with our human faith, how could we possible use it for other things like healing or prosperity? It’s super important that we understand this. If we don’t know this, we will always be looking to others to pray for you. You’ll always think that they have more faith than you do, and because of that, God will act on your behalf when they pray. That’s wrong, and it’s the reason many Christians are looking to man instead of God for their answers. However; in both the cases Lord hear our and others Prayers!
Romans 12:3 says,
“Because of the privilege and authority God has given me, I give each of you this warning: Don’t think you are better than you really are. Be honest in your evaluation of yourselves, measuring yourselves by the faith God has given us. (Measure of faith the God has given us)
Hebrews 11:1,3 says, Faith shows the reality of what we hope for; it is the evidence of things we cannot see.  By faith we understand that the entire universe was formed at God’s command, that what we now see did not come from anything that can be seen.”
This scripture is not symbolic; God actually created everything with words. He spoke creation into existence, and the substance of His faith manifested into what we can now see. The Word of God has unlimited power. Each word is like a little capsule filled with faith waiting for us believers to release it in our hearts and speak it with our mouths.
Everything we see was created by words, and it is the very Word of God that holds the universe together (Heb. 1:3). Therefore, everything we see will respond to faith-filled words. They have to respond because words are the parent force.
The only reason every one of us isn’t dead from the many idle words we have spoken is because we haven’t believed every word with our hearts. Thank God that our words have to be mixed with faith and that we have to believe them from our hearts. But this should help us see a powerful truth. If we believe we are going to be sick or if we believe that we will always be poor, and then confess that with our mouths, we will get what we believe.
On the other hand, what happens when we take the faith-filled words of God and plant them in our hearts where they can take root and grow? Everything changes—no longer are we just saying “I believe that I’m healed” or “I am prosperous,” but we believe it and the faith of God is then released through those words.
There is Power of Faith-Filled Words. It’s a powerful to speak from the Word of the God and from all the Heart, Mouth, Faith, Soul and Mind that will completely change our attitude about the words we speak. More importantly, if we will get it in our heart, we will learn that words can change our life now as well as our future.