A resulting problem is "supersessionism," basically the idea that the Jews are now the "un-chosen" people, having been replaced by the church. This position ignores Paul's more nuanced, humble and even pained discussion of Judaism and Christianity in Romans, but it also ignores what it means to be "chosen" by God.
One of this morning's lessons shows that "chosen people" are not exempt from judgement. In fact, they come under greater judgement when they do not glorify God in the world's eyes, when they become complacent and worldly, when they simply think that their "chosen" identity makes them better than everybody else and exempt from God's expectations:
"When you have had children and children's children, and become complacent in the land, if you act corruptly by making an idol in the form of anything, thus doing what is evil in the sight of the LORD your God, and provoking him to anger, I call heaven and earth to witness against you today that you will soon utterly perish from the land that you are crossing the Jordan to occupy; you will not live long on it, but will be utterly destroyed. The LORD will scatter you among the peoples; only a few of you will be left among the nations where the LORD will lead you. There you will serve other gods made by human hands, objects of wood and stone that neither see, nor hear, nor eat, nor smell. From there you will seek the LORD your God, and you will find him if you search after him with all your heart and soul. In your distress, when all these things have happened to you in time to come, you will return to the LORD your God and heed him. Because the LORD your God is a merciful God, he will neither abandon you nor destroy you; he will not forget the covenant with your ancestors that he swore to them." (Deuteronomy 4:25-31)
To be "chosen" by God is to be blessed with numerous gifts to make God's love known to the world - to share God's work. It is not a "pass" to be "complacent and corrupt."
The warning that God gives through Moses in this passage is playing out in the West today, with worldly Christian traditions in decline, desperately aping the world around them in search of human approval instead of divine blessing.
But the warning also contains the promise of mercy. The covenant - for Christians, the blood of Christ - is never forgotten by God and after hardships bring us back to our (spiritual) senses, the Father waits to welcome us back.