1-Talking is forbidden when the imam is delivering the sermon on the day of Jumu'ah. This is evidenced by the Prophet's ﷺ statement: "When you say to your partner on the day of Jumu'ah "quiet" while the imam is delivering a sermon, you have indeed uttered a useless statement" [ Source: Al- Bukhari.] 2-It is discouraged to walk between seated people, except if the person is the imam or he walks to fill an empty space which he cannot get to except by walking between them.