How can they believe unless they have heard, how can they hear unless someone tells them, how can someone tell them unless they are sent?

We are called and sent to tell, that they might believe. And what is the message? Not that they are without faith, or without zeal, but that there is a more worthy object of their faith. What God has done in Christ is beyond measure and worth. All who call on him in faith will be saved. This must be a truly trusting and committed faith. When we say we believe, and then continue to try to accomplish our own salvation by works, we betray ourselves. We are called to believe and to confess – “Do not doubt, only believe…” (Mt 21:21). True belief, true faith, is acted upon. Thus James’ argument that faith without action is dead (2:26).
I love the fact that Paul affirms their zeal for God. He does not disparage them for their lack of faith, but understands and articulates how their faith is mis-directed. This is also a true challenge to the relativists- even among Christians – who give too much freedom of belief. There are some things that really do matter. There actually are some answers that are better than others. And these answers are grounded in Jesus.