This scripture (Joshua 1:8) is the key to a successful life. The first thing I want you to note is that the heart was not mentioned at all in the scripture. It says the Word shall not depart from your mouth, not your heart. This means you must continually talk the Word. Secondly, to meditate means to “say to yourself”. Thinking is not meditation; you have to say something. It may be by talking quietly under your breath or by roaring it aloud. You may have the Word in your heart, but if you don't talk it, things will not change. 

Proverbs 4:23 (MSG) lets you know that everything in your life originates from your heart (i.e. your spirit); it says, “Keep vigilant watch over your heart; that's where life starts.” The result of your life is the reflection of what you've accumulated in your heart over a period of time. The Lord Jesus said, “A good man out of the good treasure of his heart bringeth forth that which is good… for of the abundance of the heart his mouth speaketh” (Luke 6:45). Jesus is showing you that what you say controls or directs the course of your life. 

In the first chapter of the book of Genesis, the Bible reveals that God and His Spirit were there, yet the world was a chaotic mass until God spoke. God had to speak before creation leaped into being. You see, talking the Word is of utmost importance to the believer. Romans 10:10 says, “For with the heart man believeth unto righteousness; and with the mouth, confession is made unto salvation.” Put differently, a man is not saved by his believing, but by his confession. The reason is that the righteousness that is of faith doesn't keep quiet; rather, it speaks (Romans 10:6). 

God reveals Himself to you through the Word that you take into your heart. Meanwhile, the revelation alone wouldn't change the circumstances of your life. However, by the time the Word gets to your mouth and you speak it forth, it becomes rhema – the active creative Word. This creative Word is powerful and will always produce results. If you want to be a mature son or daughter of God, you must meditate on the Word; you must be a talker. 

Some people unwittingly pronounce death on their finances, bodies, and businesses on a continual basis. When the harvest of their confession comes, they're quick to blame everybody – including God – except themselves for their woes. If only such people would realize that they can use their tongues to break that cycle of death. 

If you see that your life is heading for the rocks, don't wait until you hit them. Use your tongue to turn the path of life; make a detour at the right time. There are not enough limitations in the world to stop you when you speak God's Word. All you need to do is fill your mouth with the Word of God. Keep speaking it because God's Word in your mouth is the hope for your future. If you get a hold of this truth, it will catapult you to the mountaintop where you will be gazing together with Jesus at a world full of possibilities