Simplify the following text for a Grade 9 native English-speaking person.
Original: The Second Epistle of John , often referred to as Second John and often written 2 John , is a book of the New Testament attributed to John the Evangelist , traditionally thought to be the author of the Gospel of John and the other two epistles of John .
Simplified: There is some disagreement over whether the John who wrote the letters of John , the John who wrote The Gospel of John , and the John who wrote the Book of Revelation are the same person .