The entire Bible, all 66 books, was written over a period of 1500 years. The Old Testament, from Genesis to Malachi, was written to reveal God’s plan of Creation, redemption and salvation through the coming Messiah. It is focused on the nation of Israel and prophecy. It was compiled in the B.C. era, i.e. before Christ. Remember that God first revealed himself in the Creation and then in the written Word. Malachi is the last of the books in what is referred to as the Old Testament. It was written about 400 years before the birth of Jesus of Nazareth.
After 400 years of silence, God revealed himself in the living Word, Jesus Christ. The first four books of the New Testament, called the Gospels, recorded the life, teaching, miracles, death, resurrection and ascension of Jesus. They are followed by the historical account of the establishment of the Christian Church, titled the Acts of the Apostles. After Acts, the New Testament contains 21 letters written to churches and individuals laying out the theology of Christianity and providing instructions on how to live lives that reflect the great gift of salvation bestowed upon then by the death and resurrection of Jesus, the Son of God.
The last book of the New Testament, believed to be written near the end of the first century by John, one of Jesus’ closest friends, is a vision of the risen Christ in all his glory and a view of “end times” events.
To summarize, there are two testaments, Old and New, because they reflect the times in which they were written. Together they provide a full revelation of God’s plan for mankind. They tell us about God’s nature and character, the sin nature of mankind and the need for salvation. They then explain God’s answer to man’s sin, the sending of his son, Jesus to rescue mankind and provide a way for individuals to be brought back into a relationship with God.
The two Testaments tell us all we need to know to receive God’s gift of love and grace in Christ to gain eternal life. The Bible is truly the operating manual for life and is Best Investigated Before Leaving Earth.