Genesis is the book of beginnings. There are five critically important beginnings in Genesis chapters 1-12, the last of which is the beginning of a new nation which will be established through the seed of Abraham.
That nation will be the means through which God will accomplish his purpose for the earth in accordance with God's two-fold purpose for the universe.
In the book of Genesis, we also see the four divine institutions which have been established by God for the successful functioning and orderly maintenance of human society.
In Leviticus 23, Israel's seven feasts provide a remarkable prophetic picture of Israel's calendar of redemption, and in Leviticus 26, Israel's entire history is prophetically outlined in the five courses of punishment which Israel will experience before their kingdom program is ultimately established.