It’s an interesting discussion. A couple of things:
First, as I say, it’s not clear to me how much of this notion of hell comes from the Bible as vs. Greek mythology. The Bible has virtually nothing about hell, and virtually nothing about its location, while it seems that Greek mythology has somewhat more information on that matter.
Secondly, it isn’t clear from these quotes that hell is “at the center of the earth”. (At most it’s “beneath the ground”). It’s not even clear from the Biblical passages themselves that Christ went to hell, and if he didn’t, the Bible doesn’t seem to have any particularly robust notion as to its location.
However, as I say, the notion that hell was “down” was, I think, a popular notion in society, if not strictly a particularly Biblical one. (If for no other reason than that it made a good opposite to heaven’s being “up”).
