Silence of The Prudent

As Amos speaks of the times they are living in, just how evil and unjust it was, it would be prudent to keep silent. He's not being hypocritical by him continuing to preach because it is given to some to be spokesmen during such times, but as we are witnessing now , it could mean loss of income, physical violence against ones person, a cause of division or in some cases even death.