Adam's Sins Inherited

Why do I get punished for Adam’s sin?  That’s not fair.  Adam and Eve sinned, and I get messed up for it, because now I have this sinful nature.  Why do we have to get messed up because of someone else's sin?

How Do We Trust the Writers of the Bible?

It seems clear that the writers of the Bible were fallible men, and for some of them, they were even rebuked by Jesus as being wrong.  They had wrong ideas, they had wrong beliefs.  So how can we trust that their writings (the Bible) is the word of God?