The people still cannot understand what Jesus is talking about here. They are genuinely confused about the nature of the Christ and what He was coming to do for the world. Jesus speaks of the light being here just a little longer. They are told to walk in the light and believe in the light.
Why do people not get it? This is a problem that we still see today. Jesus is presented even more clearly in the gospel. We are living in the post-resurrection age, so that we know how the story ends. We are at a better advantage than those who are speaking to Jesus in our verses today, yet people still do not understand when presented with the facts of the Bible.
It takes more than just facts for men and women to believe. As we will see, their hearts have to be moved and changed so that they can believe the truth that is just before them. It is easy to say if we could just see God, or hear God, or have a sign from God. These folks are standing with Jesus, hearing the voice of God, knowing He brought Lazarus back to life. Yet, they do not believe.
Consider: John 3:1-8