1. God made the world, you are just a spectator in a body, you change your perceptions about it, you stay in it because it’s God’s creation (Heaven on Earth) and never want to leave. "There is no world" refers to ego perceptions of the world. The world is not believed to be an illusion.
2. God did not make the world, you are not just a spectator but a dreamer who made the world, its forms are your thoughts, your mind is bigger than the world, and beyond the world entirely is ANOTHER world (Heaven) that God created as reality. Earth is just an illusion, bodies aren’t real. There is no world.
I’ve encounted many people now and they always fall into one or the other camp. It always hinges around whether God made the world or not. Whether it’s real or not.
If you believe God made it, automatically all of the rest of what the Course says has to be adjusted to FIT that and is seen as supporting it. Various things are easily read into and seem to add verification of that viewpoint.
Some people have been studying ACIM for 30-40+ years and believe #1 (God made the world) is the ACIM teaching. They value the world, want to keep it, want to see bodies, and attempt to spiritualize it and love it and stay in it. They can’t really help this because the entire model of reality steers you in that direction when the premise is that God created Earth... "and therefore".
I do not believe #1. #1 is "false perception" and believing illusions are real. I believe #2. It is far more radical and difficult to accept. The ideas of God not having created the world are far "bigger" and mind bending. #1 is much safer and "easier" to relate to.
#2 is much more challenging and requires questioning of just about everything you ever assumed was true. That includes assumptions that you are confined to a body, the world outside of you is really there, and that the world "exists" or has happened. These aren’t easy to look at given what that implies. That there is literally no world here.
It means you made the world ("the world you made"), you are pretending to be a little body when in fact you made the whole environment, you are dreaming a universe, Heaven is another realm entirely, and everything you ever thought happened in the world did not happen - not even the world itself. It also then means you have to find a way to SEE beyond this world, to look past the illusion of forms and bodies, and leave this place to go Home to heaven where you belong.