Before modern (scientific) medicine developed, it was difficult to understand why people got sick or had accidents. Scientists showed that it was germs and infections that turned childbirth or small cuts into fatalities, and caused diseases such as cholera, TB or pneumonia.
Until then, the easiest explanation was it was due to a demon, or a witch, or some other evil spirit, or that God had cursed you because you'd sinned in some way.
Before electricity, and streetlights and outside security lights, noises in the dark could be terrifying. It might just be the wind, or a passing animal, but if you couldn't see what was happening, imaginations ran wild.
Again, it might be due to (evil) spirits intent on some dastardly deed, so best to crank up the prayers because you had few other defences.
But today we are far less inclined to suspect that it is demons that are causing sickness or making the strange noises in the night. Science and technology have taught us that you can usually find a rational explanation.
And, despite the fulminations from the pulpits, no-one has ever seen a devil. Perhaps they are just in the minds of the superstitious and those who try to scare parishioners into giving more.
We can't help but notice how ready some preachers are to blame Satan every time something happens that they disapprove of.
We no longer need demons or the devil or satan to explain the bad things that happen.