The voice on the video is one Francis Chan who is pretty widely well known these days. I've had the privilege of hearing Chan speak on one occasion, and look forward to the next in just a few short days. I apologize for the somewhat cornball editing of the video, and I'm not sure how using the title theme from "Braveheart" makes the video a "sermon jam," but be that as it may, I think Chan has some good stuff to think about here.
When I first watched the video, I wondered why it was titled "Aging Biblically." I didn't hear too much in there about how to grow older in a biblical fashion. Rather, it seems to me that what Chan was driving at is that we tend to live our lives, either in the early or later years, without a sense of eternality in view. Chan's sentiment about living our lives in such a way that shows that we do not know when we are going to meet God, and therefore arranging our values and purposes in light of that reality, is not just for the aged, but is in fact for all believers of any age.
I do think, however, that Chan hits a nerve that is very sensitive for us Christians in the West, and particularly here in the United States. We tend to view life as a process of gaining security as we age. That is, we save for retirement, we plan financially, we minimize risk, we work really hard to get those things we want (whether possessions, family members, whatever), as though we have an agenda to "make it" - at least to the extent that we've achieved and obtained those things we wanted to achieve and obtain. The question he raises, and I think it's a good one, is where do we see this pattern in scripture? The answer is we don't. As Chan says, what we see in scripture is a radical rejection of security for the sake and cause of Christ. This we do, not because we have to or because it is the cultural expectation of Christianity, but because it's worth it. Moreover, those things that can and do captivate our time and attention, especially as we get older, need to be regarded as what they are: a dung hill. Why a dung hill? Because that's what everything is when compared to the surpassing worth of knowing Christ Jesus my Lord.
What I think it really boils down to is one thing: idolatry. Loving something or someone more than we love God. For us Christians in the U.S., I think the main idol that we worship is security: the hope that my life will be OK and that it will go essentially the way I want it to. Then we take steps to bolster our hope in security by working over time, achieving more, saving more, and buying more. We also might say that our main idol here in America is the idol of our present and/or future happiness. That's why we see people hoarding and buying, and planning and saving. (see this brief article for a poignant treatment of some of the effects of idolatry)
The irony of a life committed to the idol of security is that such a life is anything but secure. As Chan says, there are no days that are guaranteed to us; we could all be gone in an instant. What then has our planning, saving, and time and energy put into worshiping the false gods of happiness and security gained us? Absolutely nothing.
Does this mean we can't or shouldn't plan for the future? Nope. Scripture likewise teaches that it is wise and prudent to plan for the future, and that working hard is right and good. I think Chan's point is that, instead of putting time and energy into things that aren't guaranteed (security and happiness), let's put that same amount of time and energy into abandoning everything for Jesus.