Complex sentence: The Gospel of John (also referred to as the Gospel According to John, the Fourth Gospel, or simply John) is the fourth of the canonical gospels, after the synoptics (Matthew, Mark and Luke).
Split into simpler sentences: The Gospel of John (also referred to as the Gospel According to John, the Fourth Gospel, or simply John) is one of the canonical gospels. In the New Testament it traditionally appears fourth, after the synoptics (Matthew, Mark and Luke).