The discourse which follows begins with a little incident of which we do not know the immediate ending. Some Greeks, Gentile proselytes seeking for the truth in Judaism, asked to meet Jesus (12:20-21) but we are not told that they ever did. They point, however, to the acceptance of the Gospel by the Gentile world, which would be the result of Jesus' approaching death and Resurrection. The work of salvation had begun among the Jews (4:22) but was about to be carried into the whole world (4:42).

When Philip and Andrew told Jesus that the Greeks wanted to see him (12 :22) he began to speak of his approaching glorification, by which he meant his death and Resurrection through which he would complete the work which his Father had entrusted to him (12 :23). The vivid saying of 12:34 reflects the ideas of Mark 4:3-8 and 26-29 in which the growth of the plant from the seed is related to the spread of the Kingdom of God in the world. The universal Church would spring up from his death and Resurrection, as the plant springs from the seed. The sayings of 12:25-26 are similar to those of Mark 8:34-38.

There is no account in John's gospel of the agony in Gethsemane after the Last Supper, but in 12:27-30 Jesus' inner agony but total obedience to the Father is shown, as he prepares for his death; the manner of his death is predicted in 12:32-33. Through his death he would overthrow 'the ruler of this world', that is, Satan or the Devil.

The misunderstanding of the crowd in 12:34 leads on to Jesus urging them to believe in 'the Light' while the Light was still with them, so that they might become 'people of the light' (12:35-36). This is the final appeal of Jesus to the Jewish crowds in Jerusalem. The people still could not see the significance of the miracles Jesus had done (12:37) and Jesus then leaves them.

The writer then refers to two passages from Isaiah which he uses as commentary on the unbelief of the Jews (12:38-41). Centuries ago, Isaiah had expressed astonishment about the lack of faith of his people (Isaiah 53: 1). All four gospel writers quote from Isaiah 6:9-10, obviously a widely used text in the early Church to explain spiritual incomprehension. It is used in Mark 4:11-12 in connection with Jesus' use of parables. John understands Isaiah as having prophesied about Jesus' death, in particular in Isaiah 52: 13-53: 12. In 12:42-43 there is a comment that there were many of the Jewish teachers who believed in Jesus secretly but who feared to show their belief publicly because of the power of the Sanhedrin (12:42-43).

Jesus' concluding words in this discourse bring together teaching from the earlier part of the gospel, that to refuse to believe in him is to put one-self under God's Judgement, but to believe in him is to know God and to find eternal life.