This seems to be a popular misunderstanding of how salvation works. It is even more confusing since the book of James speaks of faith and works in a way that can be viewed with a quick look as speaking of works being required for salvation. That is far from the truth of the matter. James and Paul both agree that Faith is by grace and that because of that grace you exhibit that sanctified status by works. Jesus said you will know them by their fruit (Matt. 7:16, 7:20). In this case, he was speaking from the other side in that you will know false prophets and teachers. Matthew 7:17 indicates he means it in reciprocation, too. We have phrases like “walk the walk” and “actions speak louder than words”. That is exactly what James is talking about. You can believe and have faith but true faith will exhibit itself through the fruit that you produce. Fruit is obviously being used metaphorically.