Let us posit that I am hovering, arms flailing, in a state of abject panic, 45 degrees off the edge of a cliff. Forget gravity (for the sake of this experiment, gravity doesn't exist). Instead, let's look at god's will as the sole determining causal factor in whether I:
(1) recover my balance, or
(2) plummet to a screaming, squishy death.
Now, if I recover my balance, is that consistent with god's will?
Now if I fall to a screaming, squishy death, is that consistent with god's will?
Well, if god is omnipotent, as is often claimed, then both are consistent with god's will. Indeed both at the same time are consistent with god's will, and neither at the same time. God could also whisk me up into the skies, never to see the ground again. If God so desired I could hang, terrified, there forever. So, god's will "explains" every possible (and even all logically impossible) outcomes.
This tells us something very important about god's will as an explanation. It actually permits all possibilities and, therefore, prohibits none. Clearly there is no possible result that is inconsistent with an omnipotent god. And that, folks, is precisely why god's will offers us zero predictive power. We cannot say, of any result, that it contradicts god's will.
That's quite a versatile "explanation" indeed. So versatile, in fact, that it doesn't give us anything to use to choose between different outcomes. Some folks find this feature to be compelling. Who doesn't like unlimited possibilities, after all?
So, using god's will, let us ask again, will I recover my balance or will I fall to a screaming, squishy death? It seems the only answer is, "We don't know." Well, as someone teetering in abject terror, I am intensely interested in any predicted results here. I am very much interested in whether I recover or fall to a (you know the rest)...
Theory vs Explanation
A scientific theory is specifically designed to offer predictive power. That means science's "explanations" require some results and prohibit others. The prohibiting other outcomes is referred to as "falsifiability." Falsifiability is the naming of outcomes under which a theory would be proven incorrect. If a scientific theory prohibits an outcome and it happens, then it is time to revise or abandon the theory.
This is the main difference between a scientific theory and any old explanation. Theories tell us something that we can test for. Whether you want to be able to test your explanation is another issue. Many people like composing their "explanations" so that there is no way to test them. This keeps them immune from inquiry. There are even follower-types who will gaze in jaw-dropped amazement at how clever such an explanation is. Such people can often be convinced to give you money, apparently.
"God's will" does not prohibit outcomes. How are you going to search for truth, how are you going to investigate anything, if your method of inquiry tells you nothing at all - offers you zero predictive power?
However, the matter is even worse than this, using "God's Will" as an explanatory device. Since there is no possible verification or refutation of the explanatory device, the matter is forever shrouded in impenetrable mystery. As an explanatory device, "God's Will" stops us dead in our tracks. With "God's Will" we get precisely nowhere and have no potential to get anywhere...
There are two ways an "explanation" may be irrefutable:
(1) it may be true, or
(2) it may be designed such that it can never be refuted.
To say that something is irrefutable is not necessarily to say that it is true. The latter is only interesting as an example of what not to do. It is not profound, nor wise, nor deep, nor, and this is most important, true. So, when you are confronted by an irrefutable explanation, ask yourself if it is actually true or if it is irrefutable because there is no way of telling if it is true or not.