Modern Christians often think, "Since the time of Jesus' second coming cannot be known, we need not think much about it." Mark [the writer of the New Testament's second gospel] draws the opposite conclusion: since the timing is unknown we should think about it all the time.Not to quibble with Powell, but I think Mark got this conclusion from Jesus Himself.
Be that as it may, Powell makes an important point. We modern day Christians are complacent to the point of functional disbelief when it comes to Jesus' promise of a second coming, when He will end the life of this time-bound, sin-bound universe to usher in "a new heaven and a new earth."
That isn't to say that Christians should get caught up in speculation about when Jesus will return. The very words of Jesus that Powell explores tells us that only God the Father knows when Jesus will return and that all the conditions for that return had already been met in Jesus' generation.
But how might it affect the lives of Christians if we really believed and lived out of the belief that Jesus could return at any time? Even right now?
How would it change our priorities?
Would it cause us to live with less fear?
Would it cause us to be less concerned for ourselves and more concerned for the physical and spiritual needs of our neighbors, not to mention Christ's call to treat them with love and justice?
Those are good questions to ponder, I think.
(By the way, thinking about and believing in the End that Jesus promises will come is not to be confused with "rapture theology," a la Left Behind. See here.)