Meanwhile, I know God exist inasmuch as I know I exist and that other people I encounter in real life also exist. I also know he cares about me in a similar way that I know other people who are close to me care about me. For me to say I’m not certain God exists would be in the same argument of positing that I don’t really exist nor any of my family or friends.
That is to say, I’m much more certain that God exists than I am that you do, because you could actually be Skynet.
To explain why I’m certain would probably be one of these outer circles: