'Envoys' in the Bible

So Ahaz sent envoys to Tiglath-pileser, king of Assyria, to tell him, "I am your servant and son. Save me from the king of Aram and the king of Israel, who are attacking me."

But the king of Assyria uncovered a conspiracy involving Hoshea, who had sent envoys to King So of Egypt and stopped offering tribute to the king of Assyria, as he had done annually. As a result, the king of Assyria placed him under arrest and sent him to prison.