The chapter calls those who come "my consecrated ones" (13:3). Does that mean they were serving the LORD?

The chapter calls them his: "I have commanded my consecrated ones; yes, I have called my mighty men for my anger" (13:3). Two verses on, "They come from a far country, from the uttermost part of heaven, even the LORD, and the weapons of his indignation, to destroy the whole land" (13:5), and later, "I will stir up the Medes against them" (13:17). In Hebrew consecrated is qadash, which Brown-Driver-Briggs gives as "be set apart, consecrated" (tap consecrated). The chapter doesn't say whether the Medes knew the LORD, or what they meant to do; it says of them only that they "will not value silver, and as for gold, they will not delight in it" (13:17). Chapter 10 has words about Assyria: "Alas Assyrian, the rod of my anger" (Isaiah 10:5), then "However, he doesn’t mean so, neither does his heart think so" (Isaiah 10:7), and "I will punish the fruit of the willful proud heart of the king of Assyria" (Isaiah 10:12). Jeremiah says, "The LORD has stirred up the spirit of the kings of the Medes, because his purpose is against Babylon" (Jeremiah 51:11). Chapter 13 says nothing like 10:7 of the Medes, and these notes don't say whether chapter 10's words fit them; they set the verses side by side and add nothing.