He said to him, "Most assuredly, I tell you, hereafter you will see heaven opened, and the angels of God ascending and descending on the Son of Man."

 The second of the great Johannine key-words which we meet here is the word light. This word occurs in the Fourth Gospel no fewer than twenty-one times. Jesus is the light of men. The function of John the Baptist was to point men to that light which was in Christ. Twice Jesus calls himself the light of the world ( John 8:12; John 9:5). This light can be in men ( John 11:10), so that they can become children of the light ( John 12:36), "I have come," said Jesus, "as light into the world" ( John 12:46). Let us see if we can understand something of this idea of the light which Jesus brings into the world. Three things stand out. 