It’s good that you bothered to state that, because… I was tempted to say … 
What is commonly known as “maturity” is actually the balance between influence and personal responsibility.
It is unquestionable that literally every single thing in the universe is merely the result of whatever came before it. Yet that doesn’t actually resolve the issue of what to do about it.
The very popular, and even very predominate amongst the leaders, mindset is that, in order to maintain order, we must BLAME each individual for anything unacceptable associated with that individual. That is the reality. It doesn’t actually matter much as to why. That is just the way it is … currently.
In an actually mature society (as if such a thing has ever existed), the thing called “fault” is only relevant when it is something that can be changed by the knowledge that it was Response-Able and that there is something that could be said or done to alter the former response (is the accusation and/or condemnation actually going to fix anything?).
In most cases, by far, punishment does not help to fix the response problem, with the exception that others watching the punishment (or at least believing that it took place) become more frightened, and thus more leery/insecure, of potentially perceived violation of ordained protocol. It is a manipulation tool to prosecute, even the innocent, so as to frighten the average into compliance. And it isn’t going to stop merely because you state it publicly. It never has, for thousands of years and hundreds of generations.
The simple truth is that it is impossible to be free from causality, yet it is immature to not attempt to get reasonably intelligent people to conform to common respect. It doesn’t really matter if your intentions are good or totally malevolent. What matters is really only whether they cooperate or not (something that you, amongst many, do not do well enough) … regardless of any reasoning involved.
Blame and punishment are only inspired by the effort to get people to cooperate in a way that certain kinds of people wish to take place. Other kinds wish for cooperation yet do not punish people for not seeing their wisdom or desiring to participate at that time.
Is it really the existence of “freewill” that you question, or is it the condemnation that comes from the belief in it that you abhor? In the extreme analytic sense, “freewill” has never existed. In the social condemnation sense, the blame for misusing your freewill is the only thing that the mindless apes governing your world can use to control you… other than chemicals and military action.
What has been called “The Devil” is whatever it is that causes you to behave contrary to your own wisdom. By the disbelief that there is a “Devil”, you have invited the condemnation to fall upon yourself, else who else is there to blame?
Solution:
Fully believe in, and fully promote the accurate understanding of, “The Devil”. Then the condemnation will fall a little differently … and real progress might begin.