The one negative to horror is that it's always law of diminishing returns. When you go in the funhouse, the ride is never scary the second time. You will never have that pure experience as when you first watch it.
In my book, The Sins of Scripture, I traced the development of tribal religion, which included ideas like God's killing the Egyptians because they hated the chosen people. Then a God of love finally appears in the Book of Hosea, about the 8th century. A God of justice appears in the Book of Amos in the late 8th century or early 7th century.