Here are the readings for the week:
http://www.usccb.org/nab/101908.shtml
We're all familiar with the traditional interpretation that supports the separation of church and state: "Give Caesar what's Caesar's and give God what's God's."
But I don't find that particularly helpful. Reality is messy, and our values inform our actions and our political perspectives too. This gospel reading shows the Pharisees and the Herodians (the religious AND political leaders) trying to trick Jesus into a no-win answer. Jesus, in his wonderful way, answers their question with one of his own.
There's a deeper question beneath, I think.
Is there anything on this earth that isn't God's?