That evening, at sundown, they brought to him all who were sick or possessed with demons. And the whole city was gathered together about the door. And he healed many who were sick with various diseases, and cast out many demons; and he would not permit the demons to speak, because they knew him. 

Again, we are clearly dealing with an eye-witness account here. The detail is vivid. The afflicted are brought to Jesus at sundown, presumably in order to first complete the sabbath observance (Jesus has not long left the synagogue). The assembled throng of demon-possessed and sick townspeople gathers around the door to Peter’s house. Mark tell us that ‘the whole city’ seeks the healing of Jesus.

These verses form a bridge to a new phase in the narrative, so Mark is doing some summing-up and, also, hinting at what is to come. Jesus’ fame has grown through his teaching and healing, and now we see a mass response. Jesus heals both the body and the spirit. The variety of diseases that Jesus heals is meant to point to his divinity. He is not just a specialist physician – only healing, say, leprosy – or a kind of sorcerer; he is a genuine miracle worker.

The demons’ knowledge of Jesus creates both irony and tension. As we go, we will find repeatedly that the demonic powers have a deeper understanding of Jesus’ identity even than his disciples. The tension lies, then, in our response to Jesus. Knowing who he is (the Christ and the Son of God) will not be enough – we will have to make a deliberate choice to follow him or not. This provides the clue for understanding Jesus’ command that the demons speak nothing of him. They may know him (or about him), but they do not follow him; and Jesus desires neither knowledgeable evil, nor even the acclaim of astonished crowds (back to verse 28), but costly faith.