What do you think about when you have nothing in particular to think about? When your thoughts wander, where do they wander? In this text Paul famously says we are to "take every thought captive to obey Christ." What does that mean? Christians often use the word "worldview." What is that, and why is this text often used to support the idea? Grace changes not only our status and future destiny, but also our thinking. What does that look like in daily life?   
The ESV heading over this text is "The Cheerful Giver," a phrase that can easily be misused to guilt people into giving. But the much more important question is why? This text is about our motivation for all the Christian life, not just stewardship. Why should Christians be the most cheerful people on the earth? Why are we so often not?
This section continues Paul's discussion of generosity as one of the fruits of grace. The backstory is the collection of a financial gift for impoverished Jewish Christians in Jerusalem. Will the Corinthians participate? Why should they? What are the right and the wrong motivations for generosity?