He wants the Jews to stop talking about what they believe and do something that demonstrates it. And he tells them they will be punished if they don't. Now this approach to change works for some. The fear of an audit and the prospect of jail keep most folks honest on their taxes. I doubt that progress in civil rights in this country would have advanced very quickly were it not for sit ins that demanded a change in who could be served at lunch counters and marches that indicated there would be an angry public to deal with if change didn't happen.
Bad behavior has negative consequences.
Knowing that is enough to make some folks change. It doesn't work for everyone. Prison officials tell us that the death penalty is not a deterrent to murderers. Most people who serve jail terms do not change their behavior for fear of going to jail again. That's why they have programs that rehabilitate folks from the inside out.