How do you get saved? Notice in Romans 10:10 you believe with your heart and confess with your mouth. So, unless you followed that process you are not saved. Notice, that word confess means to say the same thing. So, you have to believe something from the word and say it to be saved. But, not just saved as in born again because that word saved if you look in the Strong's Concordance means healing, deliverance, preservation, do well. Notice, all those things are connected to your mouth(words). And The Bible shows that for Proverbs 12:6&18 says, "The mouth of the upright shall deliver them" and "The tongue of the wise is health(healing)." And Proverbs 14:3 says, "The lips of the wise shall preserve them." All those things are tied to your words so your words are very important. Especially when they are in line with God's word.
Your words are suppose to be doing something and they will be either for you or against you. Jesus said you will give account for every idle word you speak in the day of judgment. For by your words you will be justified or condemned (Matt. 12:36,37). That word idle is tranlated non working. So, your words are suppose to be working. Whether you know it or not your words are producing in your life either for good or bad. Proverbs 18:21 says, "Death and life are in the power of the tongue: and they that love it shall eat the fruit thereof." Notice, there's fruit that comes by the words of your mouth. Now, I see why God told Joshua, "This book of the law shall not depart out of your mouth; but thou shalt meditate therein day and night, that thou mayest observe to do according to all that is written therein: for then thou shalt make thy way prosperous, and then thou shalt have good success." All those that label things prosperity gospel did you notice God gave him the instructions on how to prosper. So, if God tells you how to prosper why is it such a dirty word. Especially when the word says God has pleasure in the prosperity of his servants (Psalm 35:27). You don't have to look far to know it's God's will when in the very first book of the Bible in the very first chapter when God made man He blessed him to prosper.
Well back to Joshua, doesn't that agree with Proverbs 18:21 that says you will eat the fruit of your lips. His words(by God's words) was making his way prosperous. After all God says, "I create the fruit of the lips." Well, it's his word that's doing the producing like He said in Isaiah 55:11, My word shall not return unto me void, but it shall accomplish that which I please, and it shall prosper in the thing whereto I sent it. How does God's word get returned to him when you speak it. In fact, the Bible speaks of those that don't speak the word, "If they speak not according to this word, it is because there is no light in them." Because Psalm 119:130 says, "The entrance of thy word giveth light." And Jesus said, "But those things which proceed out of the mouth come forth from the heart", so you speak according to what is in you. So, according to the scriptures people that are against speaking the word it's because the word is not in them. But, the word is meant to be spoken.