We must not make the mistake of thinking that Jesus' family found out that he did not have time to eat with his disciples and that they thus came to seize him because of their concern for his diet. Most likely, his family simply heard that he was back in Capernaum. This news would have taken maybe a day to reach them in Nazareth.
21 And when his family heard it, they went out to seize him, for they were saying, “He is out of his mind.”