The season of Advent begins this coming Sunday, and one of the readings for the season, from Matthew 24:37-4, tells of the end of time, in which Two men will be out in the field; one will be taken, and one will be left. Two women will be grinding at the mill; one will be taken, and one will be left.

One perfect early autumn day, September 11, 2001, the great city where I live was getting into full swing—almost all its workers at their posts, the morning news programs coming to a close—when everything was suddenly suspended. A man I met once told me he was coming up from the subway as the first plane hit his office building; he was just a little late for work because he had to take his child to school. This made him the sole surviving member of his company’s work force at the World Trade Center.

Our memories of 9/11 are mostly of its aftermath: the horror and grief; the heroism and endurance; the swift recovery of normal life. But we should not forget the way that awful day began: the sudden suspension of normal life, affecting everyone; the violent disruption of the flow of time; the way our vast metropolis momentarily stood still.

That is just the kind of experience Jesus invokes as he describes the Day of the Lord, that great and final day. He asks us to imagine the sudden suspension of normal life, the violent disruption of the flow of time, which we remember from that perfect early autumn morning in New York. He asks us to imagine this as possible at any time: Therefore, stay awake! For you do not know on which day your Lord will come.

All human beings suspend their normal lives deliberately, and disrupt the flow of time peacefully, when we go to bed at night; or take a nap; or go on a vacation. It is a necessary part of life. For those who live in the country, the rhythm and cycles of nature reinforce this human necessity to suspend activity and to be still periodically. But we who live in the “city that never sleeps”—this huge, complex mechanism that keeps rolling on with scant regard to nature or to man’s necessities—we New Yorkers have to be especially vigilant to make time for ourselves, for other people, and for God. We must not wait to be forced to do so, as we were on 9/11.

It would be a mistake to think that Jesus wanted to inform us in detail about the end of the world: The details of it—the “who, what, when, where, and how”—are really unimaginable, even more so than the prospect of two big airplanes being flown into the tallest buildings in New York before it actually happened. Jesus wanted us to realize that our normal lives, our daily flow of time, our work and our preoccupations, our projects and our worries—all that constitutes our everyday existence—are conditional upon God’s will for us to carry on as usual until he chooses to suspend our normal life and disrupt the flow of time, at any moment, late or soon.

Living in a city, with its concentrated energy, its impetus, and pace, makes us likely to become so absorbed in its frenetic tempo as to forget that there is One on whom it all depends, One who could suspend and disrupt it if he chose at any moment. Forgetfulness of God risks placing us together with the man or woman in the gospel who was left behind.

The man who is the sole surviving member of his company’s workforce at the World Trade Center told me he was haunted by the question “Why was I left behind?” He had spent many months since 9/11 trying to construct an answer to that question; trying to put meaning into life beyond the normal; trying to open up his mind and heart to the One on whom all life depends. He considers that God met him on that awful day and called him from absorption in the frenzy of “world trade” to make time for himself, for other people, and for God.

That is the kind of vigilance our Lord means when he tells us, “Stay awake,” and “Be prepared.” One day every week we go to church, and maybe try to keep some kind of Sabbath all day long—a day for God, for other people, and for ourselves. The Sabbath Law was given so that we could break the flow of time, and suspend the work and worries, the preoccupations and the projects, of our weekday lives in order to restore their proper balance; to recall our dependence on the providence of our Creator, and our membership with one another in the family of God.

So much in weekday life throws off that proper balance; habituates us to competitive relationships with one another; and subjects us to control by schedules, plans, and expectations. How much we need—not every week but every day—to be reminded that our world is not in our control, nor in anybody else’s but the One who made it and provides for it. How much we all need to incorporate the Sabbath rest into our daily lives, to call “time out,” even for a moment, periodically, and give that time to God, to one another, and to ourselves.

If we neglect to do that on our own, we can be sure that God will do it for us; he will call “time out” on us through circumstances and events that suspend our normal life and disrupt its flow of time. God willing, it may not be something as horrific as what happened on September 11, 2001. But for each of us, it will be something—an illness, or an accident, an interruption or a loss; and for each of us, as for the world, someday God will call “time up.” On that great, final day, may each of us have lived our lives in such a way as to put us among those taken to God’s kingdom, not left behind.