I'm so glad to see that science is beginning to catch up and agree with the Word of God. I heard about this book from a ministry associate of mine and read a borrowed copy and have just ordered one for my own. What Dr. Leaf teaches in this book is exactly what the Bible has taught for centuries--that our lives are for the most part a byproduct of the way we think, what we hear, what we say, and what we believe. Sadly, these principles have been "spiritualized" in the modern church that focuses more upon religious rituals and outward discipline rather than the practical aspects of God's Word. One may accuse the writer of promoting the "power of positive thinking" but a very quick study of God's Word will reveal these things to be true.
One reviewer mentioned there were no "practical methods" to implement these truths. I disagree, but the Word of God has an abundance of information on this subject. In a nutshell, if a person focuses his/her mind and affections on God and His infinite goodness, the byproduct of this is life and peace. The world around you may be in utter chaos, but within your heart the peace of God allows you to be victorious over any and all situations--including sickness and disease. One may assert that a person cannot be mindful of God throughout our busy days, but you can. It's true that we worry about things and still are able to accomplish daily tasks, so why not simply "worry" about the things of God. All worry is is meditating on the wrong thing. This is what it means to "pray without ceasing..."
"Be not conformed to this world, but be transformed by the renewing of your mind that you may prove what is that good and acceptable and perfect will of God." [Romans 12:2]
"As he thinks in his heart so is he." [Proverbs 23:7]
"You (God) will keep him in perfect peace whose mind is stayed on you because he trusts in you." [Isaiah 26:3]
"For to be carnally minded is death, but to spiritually minded is life and peace." [Romans 8:6]
(Read also Joshua 1:8; Philippians 4:6-9; 2 Corinthians 10:3-6; Colossians 3:1-4)
Jesus said, "According to your faith be it unto you." [Matthew 9:29] and "Go your way, and as you have believed so be it done unto you." [Matthew 8:13] The Lord also said, "For by your words you shall be justified, and by your words you shall be condemned." [Matthew 12:37] and "Take heed what you hear..." [Mark 4:24]
"Death and life are in the power of the tongue, and them that love it shall eat the fruit thereof." [Proverbs 18:21]
Read also James 3:1-6 to see that the tongue (words) control and influence our bodies in the same way a bridle is used to control a horse, and a helm is used to steer a ship. (also 2 Corinthians 4:13)
One might say, "I don't believe this." Well, it won't work for you because a person's life is based on what they believe. Not believing in this simply means that a person is believing something else--contrary to what God's Word says.
What makes this book great is that it doesn't speak "religious" language that turns off secular and non-Christian people. I pray for the day that the academic and scientific world will finally admit that what the Bible teaches is true.
By the Grace of God I Am What I Am (Study Guide & Workbook)