The Bible is not a history book — although it contains an accurate record of some history. The Bible is the account of the Old Covenant and the New Covenant that God made with human beings. The Old Testament is concerned with the period of the Old Covenant and the New Testament with the New Covenant. God made the Old Covenant with the Israelites, as described in Exodus 19:3-6. There is a very brief account of the period from Adam to Moses, designed to inform us why a covenant was needed and why God chose the Israelites to receive it. He didn’t choose them because they were a wonderful people, but because they were the descendants of faithful Abraham, who is described as the friend of God. The nation of Israel entered into the covenant, promising that they would obey God’s commands, being sprinkled with the blood of animals as a sign of how serious they were. However, they failed lamentably to keep their word. God warned them through a series of prophets that they would be taken into captivity, and he told them in Jeremiah 31:31-34 that he would introduce a New Covenant with a stronger emphasis on forgiveness. When they returned to Israel from captivity he sent the prophets Zechariah and Haggai to encourage them, and during the time of Ezra and Nehemiah they responded better to him. However when the influence of these prophets faded, the Israelites turned away from God and he finally sent Malachi to rebuke them. The latter part of the Old Testament is an account of how God tried and tried and tried to get them to turn from their wicked ways and hold fast to the covenant that they had entered into. When there was no response from them, he did as he had warned in Micah 3:6-7, and there was “no answer from God”, until the next prophet, who was John the Baptist.
The Gospel writers give us details of the New Covenant, which came through Jesus Christ. Anyone has the opportunity to enter into this New Covenant by believing in Jesus Christ and being baptized.