IMO, it's a crisis of faith, which is "normal".
"open to the idea that God is there," though not in the same fashion he was raised to believe.
As a long time Christian, I can't say I blame him. While I did not stop believing that there is a "God", I stopped believing in some of the things I was taught when I was younger about God and faith. One only has to look at history and too many religious leaders today to know that religious leaders can be corrupt and only too fallible.
I try to live by the grace of God and "to love others" as God commands. That's really in a nutshell all you need to know about God and how you are supposed to live your lie. Everything else is just man made dos/don'ts.