In his typically succinct style, Mark follows Jesus' pronouncement of the Kingdom of God, and the calling of the first disciples, with an immediate and bold demonstration of Jesus' power and authority. Jesus goes directly to the established center of faith in an observant Jew's life - teaching and exhorting the Torah during Sabbath synagogue services.
What concerns the gospel writer here is not the content of Jesus' message. We are told nothing about what Jesus said or what texts he read. For Mark the significance of Jesus' teaching is the authority with which he speaks (verse 22) and the power of his words, different in tone and texture from the traditional interpretations of the scribes. These professionals followed established scholarly procedures in interpretations of the Torah. They d…