The Bible has a lot to say about the power of words.  By the word of His power, God created the entire universe.  By the Word of God, mankind was created in His own image, a living soul, a speaking spirit, with power to affect his environment by his words.  With his words, Adam named the creatures of the earth, and whatsoever Adam called them was their name.
God had given Adam dominion over all the earth and everything in it, and that by the way included dominion over the devil.  What?  You didn’t know that?  Let me show you:
Gen 1:24  And God said, Let the earth bring forth the living creature after his kind, cattle, and creeping thing, and beast of the earth after his kind: and it was so.
Gen 1:25  And God made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind: and God saw that it was good.
Gen 1:26  And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.
Gen 1:27  So God created man in his own image, in the image of God created he him; male and female created he them.
Gen 1:28  And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.
    Here we have the precedence of man’s dominion over all the earth and everything in it.  We know that Satan had been cast out of heaven and banished to the earth sometime in the past, so before Adam was created, Satan had been the god of the earth.  We also can see a gap between Genesis 1:1 and Genesis 1:2 that in conjunction with other scriptures that indicate that Satan had destroyed the earth sometime in the past and God restored it.  Now, with Satan still on earth, God created Adam and to add insult to injury, put Adam in charge over all the earth.  Satan was not a happy camper about this, no doubt.
    At some point in time, and I would imagine it was pretty quickly after Adam came on the scene, Satan took the form of a serpent, a SPEAKING serpent at that, and came speaking to Eve, telling her that God was holding out on them by denying them access to the tree of knowledge of good and evil.  And before long, Satan deceived Eve into desiring and taking of the fruit of the forbidden tree.
   Remember I said that mankind was given authority over Satan?  Let me show you how and where that happened.  But first, let’s look at what led up to Adam and Eve eating of the forbidden fruit.  It’s found in Genesis 3:1-7

Gen 3:1  Now the serpent was more subtil than any beast of the field which the LORD God had made. And he said unto the woman, Yea, hath God said, Ye shall not eat of every tree of the garden?
Gen 3:2  And the woman said unto the serpent, We may eat of the fruit of the trees of the garden:
Gen 3:3  But of the fruit of the tree which is in the midst of the garden, God hath said, Ye shall not eat of it, neither shall ye touch it, lest ye die.
Gen 3:4  And the serpent said unto the woman, Ye shall not surely die:
Gen 3:5  For God doth know that in the day ye eat thereof, then your eyes shall be opened, and ye shall be as gods, knowing good and evil.
Gen 3:6  And when the woman saw that the tree was good for food, and that it was pleasant to the eyes, and a tree to be desired to make one wise, she took of the fruit thereof, and did eat, and gave also unto her husband with her; and he did eat.
Gen 3:7  And the eyes of them both were opened, and they knew that they were naked; and they sewed fig leaves together, and made themselves aprons.
    Something to notice here: Satan had no power to force Eve to take the fruit, because he was stripped of all his authority when he was put on earth.  He could only SUGGEST to Eve that she wanted to eat of the forbidden tree.  And by deceiving her, he accomplished the feat which caused Adam and Eve to transfer the authority that God himself had granted them, unto Satan.  Now it was their WORDS he wanted to become the master of, for he knew their words had authority on earth.
 So, what happened next?

Gen 3:8  And they heard the voice of the LORD God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the LORD God amongst the trees of the garden.
Gen 3:9  And the LORD God called unto Adam, and said unto him, Where art thou?
Gen 3:10  And he said, I heard thy voice in the garden, and I was afraid, because I was naked; and I hid myself.
Gen 3:11  And he said, Who told thee that thou wast naked? Hast thou eaten of the tree, whereof I commanded thee that thou shouldest not eat?
Gen 3:12  And the man said, The woman whom thou gavest to be with me, she gave me of the tree, and I did eat.
Gen 3:13  And the LORD God said unto the woman, What is this that thou hast done? And the woman said, The serpent beguiled me, and I did eat.
Gen 3:14  And the LORD God said unto the serpent, Because thou hast done this, thou art cursed above all cattle, and above every beast of the field; upon thy belly shalt thou go, and dust shalt thou eat all the days of thy life:
Already in verse 12, Adam was speaking words of strife and blame, blaming GOD for giving him Eve.  Imagine that!  And the woman blamed the serpent.  And the serpent didn’t have a leg to stand on!  Take a GOOD LOOK at verse 14:  read again what God said unto the SERPENT, THE CREEPING THING, then look back again at Genesis 1:26 and you can clearly see that before sin ever occurred, God had already made provision for man to exercise dominion over the SERPENT, THE CREEPING THING.  You say you never noticed that before?  Most people don’t, and I would not have noticed it either, except that back in 1998 when delivering a sermon about man’s dominion over all the earth, the LORD revealed it to me, and it changed my whole life right then and there.  In fact, when I got hold of it, I stood there silent for about three minutes taking it all in.  And until this day, the devil still tries to get us to use our words to bring his will to pass on earth, and that will is destruction, but we can beat him at his own game.
    You see, there’s nothing on this earth the devil wants more than to use YOUR mouth, speaking YOUR words of authority to get his dirty work done.  The heavenly Father didn’t take our authority away from us, even though we sinned against Him, so our words still have all the weight over the creation they always did.  But since the fall of mankind, our words have been perverted.  We should be speaking of the glory of God, but instead, we listen to the devil’s lies, and most of us use our words to hurt not only ourselves, but others.  We speak of sickness, poverty, jealousy, anger, rage, envy, because we have been spending too much time listening to the devil, instead of listening to God.
   If you take a day and record everything you say, then go back and listen to it at the end of the day, you’ll pretty quickly see what’s in your heart, for “out of the abundance of the heart, the mouth speaketh”, as the Lord Jesus said.  I’ll bet you don’t pay real close attention to everything you say, because if you did, you wouldn’t say half the stuff you say.  “Oh, that scares me to death”, “I’m so sick and tired of my job”, “I just can’t get well”,  “I just can’t seem to get ahead”.  IF YOU REALLY LISTEN TO YOUR OWN WORDS, YOU’LL FIND MANY OF THEM LINE UP WITH THE DEVIL’S WILL FOR YOU.  So, how do you beat the devil at his own game?  Stop speaking for him!  I said, STOP SPEAKING FOR HIM! 
   If you will watch your words and speak only what God says about you, it won’t be long until your life takes on a whole new face.  Do you want to be well?  Stop saying you’re sick.  Start saying “I’m healed by the stripes of Jesus.”  Are you lying?  No, God’s Word is always truth.  Here’s something you might want to make note of.  You’ve listened to lies for so long, you may not recognize the truth of God’s Word for a while, so you’ll need to keep saying it until the truth of His Word changes you and brings you into alignment and agreement with His Word.  That may happen quickly, and it may happen slowly, but if you’ll stay at it, good and lasting changes will happen to you.  AND, don’t just speak over your health: speak God’s Word over EVERY area of your life.  That is, unless you want the devil to keep on bringing waste, ruin, and destruction into your life.
   The next time you start to speak, stop and put your mind in gear first and ask yourself, Are my words lining up with God, or the devil?  Old habits are hard to break, and it WILL take effort on your part to get your words working for you instead of against you.  And you will have to keep after it for the rest of your life, because if you don’t?  You’ll be right back in the same old rut, because that’s exactly where the devil wants to keep you.  Are you sick and tired of being sick and tired yet?  Then let’s get to work on your words, right now.  For with them, you can beat the devil at his own game!  And you’ll be smiling.  And God will be smiling with you!