‘And he came down to Capernaum, a city of Galilee. And he was teaching them on the sabbath day.'
Having left Nazareth in a hurry Jesus now ‘came down' (from the mountainside to the lakeside) to Capernaum, on the shore of the Lake of Galilee. He had already been active there (one or two of His future disciples lived there) as we learned from Luke 4:23. And He taught them on the Sabbath day (in the synagogue - Luke 4:33).