This question is addressed by Costi Hinn in his recent book, God, Greed, and the (Prosperity) Gospel (Zondervan).

(Costi, as the nephew of Benny Hinn, was raised in the bosom of prosperity gospel teaching and practice, although later came to thoroughly repudiate it, as his book documents.)

1. The prosperity gospel distorts the biblical gospel

The biblical gospel is all about God, and what he has done for us in Jesus Christ.  This is seen clearly in passages such as Rom 3:23-25; 5:8-10; Eph 2:4-10. …