Most experts agree on the details of who wrote the gospels and when they were written.
Gospel of Mark
Mark was probably the first gospel written about late AD 60’s or early AD 70’s. He was not a disciple of Jesus but was considered a close friend of the apostle Peter’s and so the gospel is believed to have been written from the oral accounts that Peter gave him. He is mentioned several times in New Testament as John Mark (Acts 12:12; 15:37; Colossians 4:10; Philemon 1:24; 1 Peter 5:13).
Gospel of Matthew
The gospels of Matthew and Luke seem to have taken Mark’s gospel as a basis for their writings. Together these three gospels are known as the synoptic gospels. (Synoptic means “taking the same point of view.”)
Matthew was the second gospel to be written. He was a disciple of Jesus, and was originally a tax collector, also called Levi (Mark 3:18; Matthew 9:9; 10:3; Luke 6:15; Acts 1:13). It is believed that he wrote his book in the late AD 70’s or early AD 80’s.
Gospel of Luke
The third gospel of the New Testament was written by Luke, who was a doctor. He had not been a disciple of Jesus. It is thought that he wrote his gospel around the middle of the AD 80’s. He said that he had set out to write and orderly account of the events in Jesus’ life, and was originally writing to one person, Theophilus (Luke 1:1-4). Luke is mentioned in other parts of New Testament as well: Colossians 4:14; 2 Timothy 4:11; Philemon 1:24.) He is believed to have used Mark’s gospel as a source of information for writing, but it is believed that he also talked to Mary the mother of Jesus in order to gain the very detailed information of the annunciation of the birth of both John the Baptist and Jesus, plus details of Jesus’ early life.
Gospel of John
The last gospel in the New Testament was written by John. He was a disciple and was known as “the disciple whom Jesus loved” (John 13:23). It has been suggested that he wrote an early edition around the AD 50’s but the main edition and epilogue later, probably between AD 90’s to AD 100. His gospel is very different from the other gospels. John’s gospel includes more doctrine than the other gospels and John emphasizes the deity of Christ. He said that his reason for writing was “that you may believe that Jesus is the Christ, the Son of God, and that by believing you have life in his name” (John 20:31).