'Spokesman' in the Bible

Therefore, thus says the Lord,“If you return, then I will restore you—Before Me you will stand;And if you extract the precious from the worthless,You will become My spokesman.They for their part may turn to you,But as for you, you must not turn to them.

“If a man walking after wind and falsehoodHad told lies and said,‘I will speak out to you concerning wine and liquor,’He would be spokesman to this people.