Matthew 6:21, "For where your treasure is, there will your heart be also."
If isolated from the rest of God's Word, there are some scriptures that could be interpreted to mean that having money or wealth is wrong. However there are other scriptures that speak of riches as a blessing. The harmony between these two apparently opposite positions is that money is neither good nor bad. It is the love of money that is the root of all evil, and many have committed the sin of loving money who don't even have a dime (1 Tim. 6:10)! The love of things (covetousness) is idolatry, and this is what Jesus is addressing.
Because it is so easy to lust after money and the things it can provide, the Lord established a system whereby prosperity is a by-product of putting God first. As Matthew 6:33 states, "But seek ye first the kingdom of God and his righteousness and all these things shall be added unto you." We should no more reject the blessing of prosperity than we should covet it, which is idolatry.
The reason for not laying up treasures on this earth is so that we will not have our hearts drawn away from the things of God. A key to success in the Kingdom of God is singleness of purpose. We don't have the capacity to do our best in two areas at the same time. If we will simply put God and His Kingdom first in every area of our lives, He will add to us all the wealth that we need. What is more valuable or important than knowing Him?
Andrew Wommack.