The Bible is linear and not just a hodgepodge of information. In general, there is a chronological flow of events from Genesis to Revelation. Realizing this order of things is critical to understanding the Scriptures. In the New Testament the gospels come first, the book of Acts is a result of the things laid out in the gospels, and the epistles are a direct result of the book of Acts.
The Gospels: Biographies of Jesus’ life
The birth of Jesus; His travels; His teaching; the choosing and training of His apostles; and His death, burial, and resurrection are presented in historic detail. While physically positioned among the volumes of the New Testament, the gospels cover events that occurred under the Old Testament. Jesus was “made under the law;” He was circumcised the eighth day; He kept the feasts, and He taught in the synagogues. When He healed the leper, He sent him to the priests to offer the sacrifice according to Moses. Jesus lived and died under the law.
In the gospels Jesus introduces the coming kingdom, setting the stage for the advent of the New Testament Church. The fulfillment of many Old Testament prophecies is recorded and verified by inspired witnesses. The first three books, Matthew, Mark, and Luke, deal mostly with His humanity; John deals largely with His deity. Even all the red letters were penned by these men.
Acts: The Church in the Bible
The Holy Ghost (the promise of the Father) is given on the Day of Pentecost, the kingdom comes, and the New Testament Church is born. This book is properly called “The Acts of the Apostles,” because the apostles “Act” on what Jesus taught them in the gospels. There is a word-for-word record of the preaching of the apostles; people are saved, and the gospel is spread. There are actual accounts of New Testament water baptism and actual accounts of people receiving the gift of the Holy Ghost.
The Epistles: The Church has mail
Romans through Revelation are letters written to churches and individuals saved by the preaching of the apostles and others in the book of Acts. The letters are not instructions telling the lost how to get saved, but are further instructions to people already saved. Nobody was baptized in the epistles, nobody received the Holy Ghost, and nobody gained entrance into the church. The epistles do not alter, reinvent, or supersede the church established in the book of Acts.