JOHN

"Behold, the Lamb of God, who takes away the sin of the world!" (1:29)

"Now Jesus did many other signs in the presence of the disciples, which are not written in this book; but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in His name." (20:30-31)

Everything that John writes is meant to show who Jesus is so that you would believe in Him and have eternal life.