יחזקאל ג:יז פירוש: רש״י

I have made you a lookout Why are you silent? Is it not as a lookoutone who is appointed over the towers to see to it that if armies come to the city, the shofar shall be sounded to warn the people to gather and strengthen themselves—that I have appointed you; to warn them to beware of retribution, so that I need not bring it upon them.