What does James 3:11 mean?

James continues making his case that human beings—including Christians—are not naturally in control of our tongues. If we were, how would it be possible for us to use our words both to praise God and to curse people created in His image? James stated what seems obvious to us now: It shouldn't be that way.

It's not just that we "shouldn't" use our words for both blessing and evil. It's that it is contradictory. It's a conflict with the nature we're supposed to be relying on as saved, born-again believers. James illustrates this with the example of a spring. Nowhere in nature will you find bubbling up from the ground a mixture of salt and fresh water. It just doesn't happen. Salt water and fresh water come from two completely different sources—just as words of blessing and words of cursing come from two completely different natures.

In the same way, a single mouth shouldn't pour out both blessing and cursing. The fact that our mouths do exactly that is evidence that we're broken.