In the seat across from me, a young girl is holding a handmade sign depicting the earth engulfed in flames. Its cartoon face is frowning, and it’s holding a sign of its own that reads, “Help Me!” Her father is standing in the aisle beside her, talking to a woman he knows from somewhere. Work, I think. He has a sign, too. There’s a lengthy quote on it that I haven’t yet taken the time to read. “Honey, show Mindy your sign,” he says, and the girl lifts it up for her dad’s friend to see. “Very nice,” Mindy says.

It’s 11:30 am on Friday, September 20, 2019. On any other Friday, at this time, the Metro Gold Line would be mostly empty. But today, every train car is filled with students, families, educators and concerned individuals. Hand-made signs abound. Today is the day of the Global Climate Strikes. Throughout the day, over 4 million people in 163 countries will gather to urge their governments to take swift action against the growing threat of climate change. These strikes are inspired, in large part, by Greta Thunberg, a 16-year old climate activist from Sweden. A few days from now, Thunberg will stand before the United Nations and chastise world leaders for their inaction and apathy. “You have stolen my childhood and my dreams with your empty words,” she will say. “…The eyes of all future generations are upon you. And if you choose to fail us, I say we will never forgive you.”

The train eases to a stop. Two teenage girls step through the doors and squeeze onto the train, but they’re talking to some friends who are still on the platform. “Come on, this is where we get on,” they say, gesturing urgently. “No, it’s not,” their friends outside say. “Yeah, it is!” they insist, and the doors close. The train pulls away. The two girls look at each other in disbelief. “Ummm…” one says. The other whips out her phone and starts scrolling with purpose. “No…no, we did the right thing.”

These climate strikes are a youth-organized, youth-led movement, which has led to plenty of criticism and a fair amount of eye-rolling. I’ll spare you the tweets and the soundbites, but suffice to say, “Why should we let kids tell us how to run the world?” has become a common refrain. Which, on a human level, I get. We’ve all read “Lord of the Flies.” There’s a reason adults are in positions of authority. But what this response fails to do is acknowledge the urgency that so many young people worldwide are feeling and are expressing. It’s bigger than just warmer temperatures and sad polar bears; to these young climate activists and millions more, it appears that the human race is heading toward certain, cataclysmic end. Greta Thunberg and millions more believe that these really are the “end times.”

For Christians especially, this should sound familiar. We’ve been here before. A lot.

The train leaves Chinatown Station and winds out and around the city center, giving us that Lego-model view of downtown Los Angeles. Twenty minutes later, I’m following the crowd out of the train station and up the escalator. I can hear the roar of the crowd as the escalator brings us to the street level, and then, all at once, I’m at the heart of it all: Pershing Square, where the strike is already underway. The square is packed; lots of weaving through gaps, lots of “excuse me.” Somewhere, someone is shouting into a microphone. Cheering erupts. I start cheering, too, even though I don’t know why. At the top of the stairs above me, a group of tie-dye-wearing teenagers has started the chant, “What do we want? GOVERNMENT ACTION! What do we want? GOVERNMENT ACTION!” People of all ages, ethnic backgrounds and socioeconomic status mill around me, more and more arriving every minute. A slightly exasperated young woman is directing us via a megaphone. “Everybody, you HAVE to keep moving down.” We do as we’re told.

From the very beginning, the Christian narrative has accounted for the end of the world. That things are ending has been treated as an inevitability. How and when, though, is less clear cut. Jesus told his disciples in Matthew 24 that “no one knows the day or the hour,” but that hasn’t stopped generations of Christ-followers from trying to nail down the particulars.

The first Christians likely believed that Jesus would return within their lifetime. Hippolytus of Rome lived in the second century and used the dimensions of Noah’s Ark to pinpoint the year of the second coming: 500 AD. Pope Sylvester III claimed it would happen in the year 1000. In the twentieth century, evangelist Harold Camping pored over the Bible and employed numerology (adding up numbers throughout Scripture) to determine the date when the world ends. Other Christians have delved deep into the circumstances surrounding the end times—what will precipitate it, how will we know, who will get raptured, that kind of thing. A lot of our modern ideas about this stuff come from evangelism films like A Thief in the Night and the bestselling Left Behind series. And, according to the Rapture Ready Index (a website that calculates how much our world looks like the one described in Revelation), based on a variety of factors like “False Christs” and “World Turmoil,” we are way overdue for the End of Days.

And yet, here we are.

I find my way to a better vantage point, seated on a wall above the crowd. Below me, a Middle Eastern family is handing out free bowls of rice and beans to whoever wants them. Another guy in a bandana is handing out stickers that say, “Make Out, Not War.” I can kind of see who is talking into the microphone—a sixteen-year-old boy from a local high school, who is thanking everyone profusely—but he’s mostly blocked by a person who’s constructed a massive cardboard cut-out of the CEO of Exxon Mobile. An entire elementary school class walks by, led by their teacher, each child waving their school flag. Jane Fonda steps up to the mic, which gets a huge reaction. She praises the young people behind this movement, and calls them “the real adults in the room.” Big applause.

In the book “Reading Revelation Responsibly,” Michael J. Gorman urges believers to engage with apocalyptic literature and prophecy in a way that is “theologically responsible, which entails paying attention to the book’s original historical and literary contexts, its relationship to the rest of Scripture, its relationship to Christian doctrine and practice, and its potential to help or harm people in their life of faith.” In other words, the book of Revelation and the topic of the end times is something that we should examine carefully. Revelation is a very specific literary genre, and we should understand its characteristics before we try to map it onto our present day.

As for the specifics of climate change, those seem pretty cut and dry. It’s an emergency . A preventable one, possibly. That’s what many are hoping.

The march begins. Thousands of people leave Pershing Square and make their way through the streets of Los Angeles. Chants start and end. Signs are held high. At one point, there’s a lull. We’re shaded by skyscrapers on either side. And then, somewhere behind me, a trumpeter begins to play, This Land is My Land. The sound reverberates off of the buildings. I feel myself start to tear up. I sing to myself, and the person next to me starts singing, too. Here we are, marching through the city, our city, singing, “This land was made for you and me…” Maybe it’s the “made” part that gets me. This earth, our days, are a gift, given by the Giver. And we don’t know the day or the hour when it will all come to a close. But until that unknown moment in time, perhaps we can try to do our very best with what we’ve been given.