"All I say is that I think it is damned unlikely that anything like a central cosmic will, a spirit world, or an eternal survival of personality exist. They are the most preposterous and unjustified of all the guesses which can be made about the universe, and I am not enough of a hair-splitter to pretend that I don't regard them as arrant and negligible moonshine. In theory I am an agnostic, but pending the appearance of radical evidence I must be classed, practically and provisionally, as an atheist." H.P. Lovecraft
The answer is quite stark and black and white. The creator of the mythos of Cthulhu, H.P. Lovecraft believed that there was nothing but stars in the cosmos, with no god or gods, and no heaven or hell. He didn't believe in anything beyond what could be proven, touch, smelled or seen. Which is why his work has a feeling of horror that extends beyond most people's comfort zone, he writes about fear in ways that alien life would present to a human. Cthulhu and all of the related beings are alien to earth, and due to their great power, humans who encounter those beings, worship them. Satan and Christian beliefs held no sway in the creation of the stories, and Lovecraft would likely have mocked those who suggested such.
(The image above shows August Derleth, HP Lovecraft, Clark Ashton Smith, and Lord Dunsany, Edward Plunkett.)
It was just for that reason that I felt more comfort reading Lovecraft and the Cthulhu worlds and mythos. I could read it and understand the concepts, the point being made, and see how the writer Lovecraft was showing his understanding of humans in their way of dealing with the unknown. As a Christian I have surely met others of the faith who would suggest it is dangerous to read unChristian material, but for me, knowing its origins, I felt completely safe that it was not aimed to weaken my faith. Lovecraft invited many other writers to participate in the evolution of the mythos. In this happening, the collective mythos took upon more recognizable good versus evil dimensions, for right or wrong. However, it was still not Christian in nature, nor was it meant to be.
"In relating the circumstances which have led to my confinement within this refuge for the demented, I am aware that my present position will create a natural doubt of the authenticity of my narrative. It is an unfortunate fact that the bulk of humanity is too limited in its mental vision to weigh with patience and intelligence those isolated phenomena, seen and felt only by a psychologically sensitive few, which lie outside its common experience. Men of broader intellect know that there is no sharp distinction betwixt the real and the unreal; that all things appear as they do only by virtue of the delicate individual physical and mental media through which we are made conscious of them; but the prosaic materialism of the majority condemns as madness the flashes of super-sight which penetrate the common veil of obvious empiricism." H.P. Lovecraft THE TOMB
And lastly, I am not someone who takes what I read lightly. I am a writer, so what I read needs to be something that comes from a place I understand, or else I worry about how it might influence my own writing. I make sure in what I do to avoid plagiarism at every turn. But it happens, even to the best writers, and I am surely not the best writer.
I have two books where I attempted to write my own Lovecraft homaged works. They are available via Amazon and in person, through me.
Sorrow of the Cthulhu Spawn
Cthulhu: Catastrophic Discoveries