Mark 1:22-24 - The people were amazed at His teaching

1:22

While Mark gives less of Jesus’ teaching than the other gospel writers, he does place a great emphasis on His teaching, and the fact that He spent a lot of time teaching. Here he notes the reaction of the people to his teaching. They were amazed because He “taught as one who had authority, not as the teachers of the law”. The “scribes” or “teachers of the Law” often spent a lot of time citing other teachers; Jesus taught first hand. Even today we can tell the difference between someone who is teaching from the heart and someone who is just giving information, or even teaching a load of nonsense.

1:23.24 

There was a man in the synagogue who “was possessed by an impure spirit”, i.e.  demon. The demon called Jesus by name, this was possibly an attempt by the demon to exert authority over Jesus. Knowing the name of someone gave you a degree of authority over that person. Clearly that was not going to work in this case. The words of the demon demonstrate the fear that the demon had, “what do you want with us”. “Have you come to destroy us? I know you are the Holy One of God”. The demon knew who Jesus was, and feared that their time was up.