Of course not. I can’t recall ever having done so other than to ask for unpublished information or similar tangential reasons. Why would you?
Few. If, I suppose, they’re concerned that the scientist has been quote-mined or grossly misunderstood in order to support a statement that in fact his publication doesn’t support. Citations are supposed to reference and support particular points. The don’t have to support everything in a book, nor are citations considered to be a claim that the authors of the work cited agree with everything in the book.
Simply whether the citation supports the statement it’s used in reference to.
We should expect skepticism. But the fact is that it’s not a scientific hypothesis but a theological hypothesis containing certain scientific components. One should expect consideration only of those scientific components. That is, only the question of whether a random person in 4000 BC could reasonably be a genealogical ancestor of all people in 1 AD is relevant to science.
Depends on the nature of the commentary, doesn’t it? In the current case, are they accusing you of quote-mining or misunderstanding? If so, are they correct? It’s really hard to have anything to say about it without specifics.