He's not insane.
What reading the Bible over and over often does is to create a sense in the reader that they have "mastered" its contents and that all of their own personal opinions and views are clearly and repeatedly affirmed in its pages.
The number of people who insist that they are able to tell you what the Bible "really" means are legion.
That isn't insanity. It's pride.
Not when you make such a public declaration of knowing when the world ends and the Bible clearly tells you that no one knows that except the Father. And he’s done it once before with the same result. What’s the definition of insanity?