My understanding of dramatic irony is that it is a literary device where the audience knows more than the characters; as in they have more information about the subject at hand. This means the words in the narrative have a more significant meaning for the readers than for the characters.
1. John introduces an example of this when the world does not recognize the Logos for what he is, John knows the mission and character of the Logos (to a certain extent) but he does not know who he is just yet either. All the while, the reader does know! (Later on in John’s writings, we see that the world does not recognize us either, even though John says we know who we are and know Jesus but do not know him fully and therefore in a sense may not really know ourselves yet fully either!)
2. This also happens when Nathaniel calls Jesus the King of Israel. This is a lofty title and was perhaps seen to be given to one who is also (metaphorically) a Son of God (my professor included these examples in his notes: 2 Sam 7:14; Pss 2:7; 89:26). The dramatic irony of course is that Nathanael probably does not yet understand that he is actually in contact with the one and only Son of God! Indeed, the true King of Israel – Yahweh embodied!
3. John 8 is a chapter filled to the brim with dramatic irony, as it centers on a debate with the Judeans about the identity of Jesus. They are asking him who he is and what he’s up to and he keeps on responding in ways that seem cryptic the audience. For example, in John 8:53 they ask Jesus, “Are you greater than our father Abraham, who died? And the prophets died! Who do you make yourself out to be?” Of course, the answer is yes, he is greater. And the readers of the book know more about Jesus and what he is up to, especially if they recall John 1. The prologue is important in light of Jesus’ statement about pre-existence in 8:58.
4. John 18:33-38 presents a dramatic irony in the conversation between Jesus and Pilate. Pilate asks Jesus in John 18:33, “Are you the King of the Jews?” Come on, that is old news in this book; of course he is! In John 18:38, Pilate says to Jesus, “What is truth?” Unfortunately, Pilate does not seem too interested in receiving an answer from the one who just said he whole mission was a truth crusade. Yet we as readers know that Jesus told Thomas that he is the Truth in John 14:6. King of the Jews – yes! What is truth – Jesus! Any other ironic questions?
5. I also detect dramatic irony in the conversation between Jesus and Mary Magdalene in the garden scene after the resurrection. John 20:15 reads as follows: “Jesus said to her, ‘Woman, why are you weeping? Whom are you seeking?’ Supposing him to be the gardener, she said to him, ‘Sir, if you have carried him away, tell me where you have laid him, and I will take him away.’ She does not know where Jesus is or who she is even talking to – but the readers know the answers to both of those things. And in due time, she would know as well. It is neat, too, because then she becomes the bearer of this information for the disciples.
These accounts enrich our appreciation by putting us in the shoes of the people of that day. It was not obvious that Jesus was God. He did not float three feet off the ground or have angels following him around. And it was not a given that he would rise on the third day. It was not as if the disciples would think he would dies, first of all, but if he did they were not expecting a dead man to come back. These considerations help paint the reality of the situation and should give us empathy for these folks.