Jesus is with his disciples in the temple and they admire the beauty of the temple. Jesus responds with the apocalyptic vision of the temple's destruction and the overturning of the world.
We are a people who aren't fond of the apocalyptic, leaving aside zombie movies. We like to think of our world continuing into the future much the same as it always has. This is why we have so much trouble with the idea of global warming. We hear the science and even see some of the effects, but it is so hard to think of giving up the second car, or no buying the tomatoes from the other side of the world, because it is what we are used to. We don't have the committment to act out of our intelectual knowledge of change.
On the other hand there are the people who say "Why bother?" If the world is going to end soon anyways, in 2012 or maybe 2013, or maybe it was last year and we slept through it. Why change? Why not continue to use plastic everything even if it is destroying the world we live in? Why not burn gas as fast as we can afford it? After all we don't really need the Gulf of Mexico, or the Arctic, or any part of Alberta outside the cities or ski resorts. Not if we don't live there.
But I figure it's like this: God gave us responsibility for this world. I expect we are going to be held to that. At some point we will need to answer for the fact that at the same time we are poisoning great swathes of creation, we are also concentrating wealth in ever bigger piles while people in the rest of the world starve, drown or die of preventable diseases. Those that aren't being killed in wars because they happen to live in countries that have something the insatiable appetite of the rich desires.
Poverty isn't going to be defeated by sending miniscule amounts of our wealth to other places to buy us some time free of guilt. It will be defeated by people who are willing to make major sytemic change in their own lives and in their communities.
So what does this have to do with the end of the world? If God is going to come and create a new heaven and a new earth, she is going to want to make sure that took proper care of the old one. Like a parent who lets their teen drive their old car. Destroying the car, either in a catastrophic wreck or by slowly accumulating dings, scratches and ignoring the warning lights will not convince your father that you should be allowed to drive the Rolls.
So whether we expect the world to end or not, whether we expect God to step in or not, we live in this world now and we'd better start taking care of it. After all that is where Jesus ends up in his talk with his disciples.