There is a very significant question that might legitimately be asked when someone sees how much I talk about Satan, because people tend to trivialize it by saying that God is so great and awesome that Satan is basically just a big nasty bug in comparison. That is a consequence of Greek thinking – find the root causes, the fundamentals, and everything else is meaningless. This is in fact as deceptive as it is useless.
OK, God is the deepest reality, He is the “mind” in which all other realities, beings and things are merely thoughtforms. Nothing exists outside of God.
However, if God is the great supercomputer that runs all of reality, Satan is a big crocodile that lives in the lake beside your village, which is the only water source. A dismissive attitude of “oh, it’s all in the mind of God” basically means that whether the crocodile eats you and your children when you go there to get water, or not, both possible outcomes will still be only thoughts in the mind of God. However, from your position, the outcome where you and your children don’t get eaten is preferable.
Another analogy is that God is the creator and maintainer of the real world, together with all the souls that live there, and Satan is the owner of a virtual reality engine, offering souls a unique experience they will get when plugged in, after they sign a release form, of course. When this virtual reality engine suppresses your memory and overrides your senses, the fact that God creates and maintains the real world will be of limited benefit to you, in your particular situation.
Yes, God is absolutely great and awesome, and yet this doesn’t make the issues I’m dealing with illegitimate, or minor. They are great and real enough that Jesus had himself crucified in order to attempt to solve them, and for Buddha to postpone nirvana in order to attempt to carve a path out of them for others to follow. One would say they are the cornerstone issues for anyone in our position, in the same way slavery is a cornerstone issue for slaves, and food is a cornerstone issue for the starving.