In the Bible, the age before Jesus Christ came to the world have been called the age of the Old Testament and the age after Jesus Christ came to the world have been called the age of the New Testament.

The Old Testament as the Law means that God gave the Scriptures through the angels as the messenger of God to the Prophets in order to make the Israelites serve to God. These scriptures are the first covenant of God, thus the Old Testament is called the first covenant as well.

By the way, the Israelites as the dependants of Abraham symbolized the chosen people of God who God had predestined as his people before God created the heavens and the earth. Thus the Israelites were God's people in the age of the Old Testament and the chosen people of God have been God's people in the age of the New Testament.

In this way the Old Testament means the first covenant as the Law that God gave to make the Israelites keep it by their mind of the flesh for their living with the flesh in the world. Thus the Law became the regulation of their living with the flesh.

By the way, their mind of the flesh have been tempted by the messenger of the devil just as the serpent in the Eden Garden tempted the mind of the flesh of Eve as the wife of the Adam.

The Israelites as the human being have to live with their mind of the flesh without their spirit that are able to follow God who is spirit.
Because the human being have been born with the dead spirit as the guilty conscience without their spirit as good conscience due to Adam's sin that followed the temptation of the serpent instead of the command of God in the Eden Garden. This is called as the original sin of human being.

And in the age of the New Testament as the age of the new covenant or the age of the Salvation, Jesus who came to the world and the apostles preached the world of truth of God as the gospel of Christ to the chosen people of God in order to save them thr