When the nation of Israel disobeys me without meaning to, the whole nation is still guilty.
The idea of a whole nation being guilty of sin before the Lord is a rather foreign concept to our way of thinking. We believe that sin is an individual issue and certainly it is, but a nation can stand in opposition to the ways of God as well.
When that happens those who follow Jesus must oppose even the nation in which they live in order to please the Lord. I suppose a rather obvious example of a national sin is the legalization of abortion in the United States. Our Supreme Court decided many years ago that killing a baby before it is born should not be illegal and therefore is not a sin! They turned our "God fearing" nation into a "killing field" of infanticide.
Many people believe that the obvious and dramatic decline in the life of the United States and it's influence around the world is because God is meeting out His judgment for our national sin of abortion!
The warning for followers of Jesus is this: Be sure to live your life according to what God thinks and not what the Supreme Court has ruled! The legality of an issue does not determine its morality!
Jesus must be Lord of your entire life and heart, not just part of it! And if your faith and the culture in which you live are completely compatible, then there is something lacking in your faith! Search your heart and your mind to see if you are holding on to a "national sin" instead of the ways of God!
"Lord Jesus show me today where my nation is sinning against you, and give me the courage to walk in Your ways and not the ways of my nation. And may You be praised forever. Amen."