'Ambassador' in the Bible

A wicked messenger falleth into mischief: but a faithful ambassador is health.

I have heard a rumour from the LORD, and an ambassador is sent unto the heathen, saying, Gather ye together, and come against her, and rise up to the battle.

The vision of Obadiah. Thus saith the Lord GOD concerning Edom; We have heard a rumour from the LORD, and an ambassador is sent among the heathen, Arise ye, and let us rise up against her in battle.

For which I am an ambassador in bonds: that therein I may speak boldly, as I ought to speak.