The main problem we have is that:
There is no precise definition for the word "God".
There is no precise definition for the word "life".
There is no precise definition for the word "love".
There is no precise definition for the word "Satan".
You may have your own personal definition of these terms. And indeed you are correct that his use of those words is therefore wrong compared to your use of them. But the problem is one of semantics. We're using words for concepts which are inherently outside of our full comprehension. Of course we will disagree with what exactly these words mean.
This doesn't mean the concepts themselves are subjective, but rather it means we can't encapsulate it all in specific words with exact definitions.
See this below:
https://en.wikipedia.org/wiki/Ignosticism