The list of things *we* have to do to get "god" to work says a lot.

Faith without works is dead because faith doesn't actually do anything, work does. This points to you/us, not any god.

And we do that work.

It's why prayer can supposedly heal something like depression, but not an amputee. Because I/you/we can do work in that department, do research, study, apply certain techniques, develop habits, alter things like our diet, exercise, surroundings, and battle such an issue directly.

WE do that work. We can say the prayer, but it's awfully convenient that, surprise surprise, we get actual results when we put in that work.

But someone who got their arm chopped off?

No prayer is going to fix that. Oh sure, there are well known scams and carny tricks, but this does not happen in reality.

And the reason is because there are no "works" that can be put in to make that happen, and thus we don't have the ability to pretend that the prayer was responsible for something that was clearly the resulting effect of our actions.