If you're not familiar with this movement, the basic idea is that, if you just have enough faith and/or sow enough seed (i.e. send money to a certain "ministry") God will bless you with wealth, new cars, new houses, etc. It must work, right? The pastors who push this "name it and claim it" (or as someone I know puts it: "blab it and grab it") crack "gospel" certainly seem to be doing well financially.
The problem is, it doesn't work for everyone. How did it work for Paul? What about John? Stephen? Peter and the other apostles? Certainly, they were faithful and gave everything for the cause of Christ, and what did it get them while they were here? What about Christians in India, China, parts of Africa, parts of the Middle East, and many other places today? They are being tortured, imprisoned and even killed for following Christ. Where is their health, wealth, and prosperity?
The fact is, God has not called us to a life of ease. He has not called us to life at all, but to death. Death to self, death to pride, death to greed:
for if you are living according to the flesh, you must die; but if by the Spirit you are putting to death the deeds of the body, you will live. Romans 8:12-13
God never promised us a rose garden. He promised us that if we follow Christ, we will be persecuted and hated. Wow, just when you thought witnessing couldn't get any harder! What a selling point for Christianity! But this is what our brothers and sisters across the globe face every day. Many of them, when they make a commitment to follow Christ, are signing their own death warrants.
What God has promised is so much better than material wealth. He has promised that when we delight ourselves in Him, He will give us the desires of our hearts (Psalm 37:4). When we truly do delight ourselves in the Lord, the desires of our hearts will mirror the desires of His heart. We won't crave fleshly things like wealth, but holiness, compassion, justice, and a closer relationship with Him. He hasn't promised us material rewards here, but hereafter.
John Piper puts it so much more eloquently than I can. Take a look at what he has to say:
John Piper Prosperity Gospel Video