...he believes he must believe in Jesus Christ and be baptized to be saved?
...he believes he can lose his salvation?
...he believes Jesus Christ is the only way to heaven for him, but isn't sure if He is for everybody?
I'm currently reading Why Believe the Bible? by John MacArthur as well as Psalms and John in the Bible. I also recently finished a biography of the apostle Paul by FB Meyer and Your Own Jesus by Mark Hall.
I would recommend all of them! :)