Which portions do you have in mind? If you’re talking about Genesis 1, that text pretty obviously can’t be “historical.” Augustine read it in ways that we would now think of as non-literal, such as seeing the “light” on the first day as a reference to the creation of the angels.
Augustine’s general hermeneutic was to interpret literally where possible. Where he didn’t, this had more to do usually with ethical than scientific concerns. (He interpreted allegorically all the time, of course, but allegory doesn’t have to replace the literal sense and in Augustine’s framework usually doesn’t). He was indeed cautious about committing Christians to things that might turn out to be rationally ill-founded, as was Aquinas. And I wish the “conservatives” on this thread would follow their example methodologically.
However, Augustine was also very slow to endorse “scientific” ideas that he thought might be contrary to Scripture. His caution extended in both directions. A recent scholar, Leo Ferrari, has argued that Augustine probably thought the earth was flat, and if he did it would certainly have been for Scriptural reasons. However, Augustine is cagey about the question, so that we can’t be sure exactly what he thought. What is clear is that he worried, as many people did, about the implications of the “antipodes” for the unity of the human race, but that he was unwilling to say flatly “a spherical earth is contrary to the Faith.” As a general principle, I think his caution is a good example to follow.
The whole issue of the “antipodes” is an excellent example of an apparent conflict between science and religion that turned out to be quite illusory. Those Christians who did have problems with a spherical earth (and I don’t know of any after the eighth century) were concerned about the implications of the idea for the unity of the human race. It was taken for granted by most people that the equator was a zone of blazing fire that could not be crossed. Even if not, it was further taken for granted that the antipodes were so far away that no one could possibly get there (this is Augustine’s objection). And it was also usually assumed that if there was land, it must be inhabited. So the standard view, suggested by Augustine for instance, was that if there were antipodes they were solely made up of water. Another suggestion I’ve encountered in the writings of St. Gregory Palamas was that the spherical earth was surrounded by spheres of water and air. The world-ocean was a kind of cosmic body of water in which the round earth floated, with the top of the earth (the part people live on) projecting out into the sphere of air.
Both of these suggestions turned out to be unnecessary. In fact, the equator is habitable, and people have been able to cross from one continent to another. The problem wasn’t with either the Biblical claim that all humans have a common origin (yes, there’s a debate now about whether we all come from a single pair, but no one questions that we come from a single population group) or the evidence for a spherical earth. The problem was with entirely other assumptions that few people thought to question.
So it may be in other cases as well.
Edwin