What is the Old Testament primarily about?
The Old Testament is primarily about Israel under the Law—the priesthood, temple worship, and God's covenant dealings with that nation from Abraham until Christ. It records how God called Abram, promised to make a nation, and used that nation to consummate His plan of redemption, with only occasional exceptions involving Gentiles.
Les explains that after the Tower of Babel, God called out Abram and made the Abrahamic covenant, promising a nation through whom He would consummate His redemption plan. From Abraham until Christ, God dealt almost exclusively with Israel, with only occasional Gentile exceptions. Israel came out of Egypt under Moses, received the Law around 1500 B.C., and the Old Testament is made up of Israel under the Law, with the priesthood, temple worship, and the Babylonian captivity—after which Ezra rebuilt the temple and a remnant returned.