The Importance of Original Sin in the City of God

Augustine: Adam and Eve were perfectly fine to begin with, but original sin corrupted their nature which they in turn passed down to posterity. Augustinian original sin is a doctrine rooted in something like a Lamarckian view of evolution that says if you spend a lot of time at the bench press your babies will have big pecs and shoulders. It's an idea that has zero scientific credibility, but Augustine was a theologian and not a scientist.