Their identity came from being called by God.  They professed faith in God.  However, their practice was nominal, lukewarm, marginalized.“Hear this, O house of Jacob, who are called by the name of Israel, and who came from the waters of Judah, who swear by the name of the LORD and confess the God of Israel, but not in truth or right.” (Isaiah 48:1 ESV)

God’s ultimate goal is the zealous pursuit of His own glory – above a beyond ours.  He did not punish His children as they should have been in order to protect His glory – not because of them, but because of Him!  Let us not be glory thieves, for it is frightening to be at cross purposes with the Creator.  “For my name’s sake I defer my anger, for the sake of my praise I restrain it for you, that I may not cut you off. Behold, I have refined you, but not as silver; I have tried you in the furnace of affliction. For my own sake, for my own sake, I do it, for how should my name be profaned? My glory I will not give to another.” (Isaiah 48:9–11 ESV)

God’s credentials:  I made you and everything else; I am unequaled and unchallenged.  “Listen to me, O Jacob, and Israel, whom I called! I am he; I am the first, and I am the last. My hand laid the foundation of the earth, and my right hand spread out the heavens; when I call to them, they stand forth together.” (Isaiah 48:12–13 ESV)

God has determined to use Cyrus to deliver His people.  God has spoken and called him as a tool of His deliverance.  God will bring him forth and prosper him in order to accomplish His purposes – This is an idol worshiping pagan.  God is in absolute control – even of godless kings!  “Assemble, all of you, and listen! Who among them has declared these things? The LORD loves him; he shall perform his purpose on Babylon, and his arm shall be against the Chaldeans. I, even I, have spoken and called him; I have brought him, and he will prosper in his way. Draw near to me, hear this: from the beginning I have not spoken in secret, from the time it came to be I have been there.” And now the Lord GOD has sent me, and his Spirit.” (Isaiah 48:14–16 ESV)

Things would have gone differently had the people listened to and obeyed God.  He would have protected them and prospered them, but they couldn’t obey.  We don’t do much better, do we?  “Thus says the LORD, your Redeemer, the Holy One of Israel: “I am the LORD your God, who teaches you to profit, who leads you in the way you should go. Oh that you had paid attention to my commandments! Then your peace would have been like a river, and your righteousness like the waves of the sea; your offspring would have been like the sand, and your descendants like its grains; their name would never be cut off or destroyed from before me.”” (Isaiah 48:17–19 ESV)