The Last line

Mr. Mullens point about the last line bugged me. The last line of Jane Eyre is "22:20 He who testifies these things says, "Yes, I come quickly." Amen! Yes, come, Lord Jesus." But the last line of Revelations is "22:21 The grace of the Lord Jesus Christ be with all the saints. Amen." Why would St. John not leave off his letter blessing his cousins? Why did Charlotte Bronte finish her book with the second to last line of Revelations? Some reasons may be that the second to last line leaves more room for extension. The last line of revelations finalizes a book, but Charlotte Bronte may have wanted to leave the reader thinking about the fate of St. John and whether he really died or not. For every place Jane visits throughout the book, there is some type of closure, whether it is going back to see her ailing aunt and cousins, to the school getting a new headmaster and improving, Thornfield Hall burning to the ground and ultimately the joining of Jane and Mr. Rochester. This characteristic of the book would be left out if the fate of St. John, a major character was left out. Although this doesn't answer the question of why the second to last line of revelations is there, it helps to understand why St. John would get the last word at all.