"'This is what the Sovereign Lord says: "This is Jerusalem, which I have set in the center of the nations, with countries all around her. Yet in her wickedness she has rebelled against my laws and decrees more than the nations and countries around her. She has rejected my laws and has not followed my decrees."'" NIV translation
After the silent portrayal of the coming judgment, God tells the people the reason for the haircut. They were the people that had been chosen to receive the instructions from the Creator of all things. They received them but then ignored them bringing this judgment on themselves.
We may ask what this has to do with us today as we are under grace and not law. The simple fact of the matter is that we still receive instruction from God through the Holy Spirit and we are responsible for listening and following Him. Our judgment is not a judgment of salvation but we will have a judgment of our works to determine our rewards.
"'Therefore this is what the Sovereign Lord says: You have been more unruly than the nations around you and have not followed my decrees or kept my laws. You have not even conformed to the standards of the nations around you.'" NIV translation
Not only did they ignore the standards of God but they didn't even live up to the standards of the nations around them. We see much the same thing today from many who profess to know Jesus. They may be God's children but they act as if they are not and don't even live up to the standards of the society around them.
"'Therefore this is what the Sovereign Lord says: I myself am against you, Jerusalem, and I will inflict punishment on you in the sight of the nations. Because of all your detestable idols, I will do to you what I have never done and will never do again.'" NIV translation
God's people and Jerusalem were meant to be a bright shining example to the surrounding nations. Instead, they turned to idols and so God is bringing judgment on them in front of their neighbors.
"'Therefore in your midst fathers will eat their children, and children will eat their fathers. I will inflict punishment on you and will scatter all your survivors to the winds.'" NIV translation
The situation in Jerusalem is going to get so desperate that people will turn to eating each other. Those that survive this horror will be scattered among the nations. We may not be used to hearing about the punishment of God but it is also made clear that this judgment is from God.