‘Many other signs therefore did Jesus in the presence of his disciples which are not written in this book. But these are written that you may believe that Jesus Christ is the Son of God, and that believing you may have life in his name.'
It would appear clear that initially this was the end of the Gospel. The next chapter may therefore have been a postscript. It may, of course, have been written immediately after, as postscripts often are, or it may have been added later, but it seems certain from these verses that it was an afterthought, for John 20:30-31 are clearly saying, ‘I have presented you with the facts and you must now consider your response'.
‘Many other signs.' He knows that they can learn of them from elsewhere, things that demonstrated the uniqueness of What and Who Jesus is. The emphasis on ‘signs', which is especially John's word for miraculous happenings (John 2:11; John 2:23; John 3:2; John 4:54; John 6:14; John 9:16; John 11:47; John 12:18), is not on ‘proof' but on ‘revelation'. They are signs precisely because they reveal the fullness of the glory of Christ. They reveal among other things that what He brings is new wine not old tradition, that He is the bread of life, that He is the light of the world, and that He is the resurrection and the life. Indeed that He is ‘the way, the truth and the life' (John 14:6).
‘In the presence of His disciples'. They were eyewitnesses to what had happened. They spoke what they knew and saw (see 1 John 1:1).
‘These are written that you may believe -'. The present tense of ‘believe', used in the majority of ancient manuscripts, stresses the continual nature of this belief. ‘That you may believe and go on believing'. John's purpose in writing was to arouse saving faith in his readers, and to confirm and strengthen the faith of those who already believed. Through believing in the revelation of Jesus Christ the Son of God men can find eternal life. Some manuscripts have the aorist (to believe once for all). It is easy to see how later, when believing was seen as ‘the way in', this change would occur.
‘These are written that you may believe that Jesus Christ is the Son of God, and that believing you may have life in his name.' Here John states the purpose of his Gospel. It was that Jesus might be revealed as both Messiah and Son of God. And as we have seen this idea has been prominent in every chapter. And the end result was to be that by believing in Him many would receive life ‘in His Name'.