A genuine question after my first 4 services – if God/Christ is omnipresent and omnipotent and all powerful, and acts of evil are prompted by the devil, then isn’t God just allowing the devil to spread evil and tacitly fine with it?

I attended four services in a month long rehab program and had a question. The pastor and my Christian peers in rehab consistently referred to works of evil being the devil. Let’s take a tragic but common scenario, innocent child gets a horrible terminal disease. They said that was the devil at work. Or if you want another hypothetical to work off of, a serial killer murders innocent victims. He was being influenced by the devil.

But then in other conversations God is all knowing, all seeing, and all powerful. So he knows the devil is going to influence such that innocent children die, he has 1000x the power needed to lift a finger and prevent it. But he doesn’t. Which is the same as doing it himself basically. Such as if you put a person in the famous trolley problem, only all they had to do was push a button and the train would switch tracks to hit nobody, but they are like meh, don’t feel like it.

I understand sometimes people have to die in the Bible, like the millions of kids and unborn babies who died in the great flood as a direct choice by God, but I thought that was to cleanse everything. Why have innocent kids die now?