one who makes public proclamation. The only notice of this officer in the Old Testament occurs in (Daniel 3:4) The term "herald" might be substituted for "preacher" in (1 Timothy 2:7; 2 Timothy 1:11; 2 Peter 2:5)
Herald
Isaiah pictures a messenger on the move: “The voice of him that crieth in the wilderness, Prepare ye the way of the LORD.” That is the work of a herald, someone sent to announce what another is about to do. The word is gathered here with three verses in which Paul describes himself. In 1 Timothy 2:7 and 2 Timothy 1:11 he says he was appointed “a preacher, and an apostle, and a teacher of the Gentiles.” The King James Bible says preacher, but the idea is of someone who proclaims news that is not his own. A herald speaks for another.
3 verses
Isaiah
Isaiah 40:3
The voice of him that crieth in the wilderness, Prepare ye the way of the LORD, make straight in the desert a highway for our God.
1 Timothy
1 Timothy 2:7
Whereunto I am ordained a preacher, and an apostle,(I speak the truth in Christ, and lie not;) a teacher of the Gentiles in faith and verity.
2 Timothy
2 Timothy 1:11
Whereunto I am appointed a preacher, and an apostle, and a teacher of the Gentiles.
From Smith's Bible Dictionary
William Smith, 1884