You have cheated me of the tithes and offerings due to me. You are under a curse, for your whole nation has been cheating me. Bring all the tithes into the storehouse so there will be enough food in my Temple. Your crops will be abundant, for I will guard them from insects and disease. In this passage the people are charged with robbing God.
Extra gifts go extra places, but the tithe goes to the church.
That tithe enables the church to be sustained, ministries to be funded, needs to be met. But not only this. Our checkbook says a great deal about our values. God is honored when we honor Him in our finances. The church gives us the opportunity to show our love for God in a tangible way through our attendance, our service and our giving.