The word of the Lord came to me: “Son of man, set your face toward the Ammonites and prophesy against them. Say to the Ammonites, Hear the word of the Lord God: Thus says the Lord God, Because you said, ‘Aha!’ over my sanctuary when it was profaned, and over the land of Israel when it was made desolate, and over the house of Judah when they went into exile, therefore behold, I am handing you over to the people of the East for a possession, and they shall set their encampments among you and make their dwellings in your midst. They shall eat your fruit, and they shall drink your milk. (Ezekiel 25:1-4 ESV)
When Judah is judged, she is not alone. The nations around her are also judged. In the case above, it is the Ammonites, a nation on their Eastern border. What is interesting to note is that Judah is judged for her failure to stay true to the Lord and walk in His ways. Judah and Israel are described as having copied the wicked practices of the nations around her, especially in the false gods they worshiped and their deplorable worship practices (which often included sexual promiscuity and child sacrifice). But when these same nations are judged, it is not for these deplorable acts. Instead it is how they related with Israel. Did they bless or did they curse Israel? That is what we see here with the Ammonites. That is their foundational sin. How did they treat the one holding the key to their own salvation? Israel was to be a priestly nation, interceding on behalf of the nations before God. They had the law of God given to them and were meant to be a city on a hill that shined the beauty and righteousness of that law to the world around them. Israel, in that sense, was a type of Christ. So it should be no surprise to see that the reason given for the nations judgment is their rejection of this Christ figure that God settled in their midst.
The same, of course, is true today. God sent His son into our midst to become the savior of mankind. While we all stand guilty for our own wickedness before God, our judgment comes on how we respond to the savior. Do we bless or do we curse? Do we live by faith in him or do we reject Him?