Basic Premise of both Sunday School and Sermon was that turning from God has consequences.
The 3rd chapter of Habakkuk was the sermon basis. I have never actually read Habakkuk. It was very interesting and particularly relevant for today, I think.
Basically, God used the Chaldeans to punish Israel for turning from him. But, the Chaldeans themselves would be held accountable for their actions.
How is that relevant for today? Is anyone really asking that?