On the Thursday before Rosh Hashana, I invited random people to share their hopes with me for two hours as I stood in the quad. I had two giant rolling corkboards with me, each with an invitation tacked to the top: Share a hope, wish, or intention for the new year. The school year just started, and the Jewish new year was about to begin. Anyone could participate in a way that was meaningful for them. 

“Do you have any hopes to share?” I called out. 

Many people did. Some people wrote specific hopes –  such as passing pre-calc. Others were more general. Some hoped for good grades, better sleep, better work life balance. An end to COVID. Health. Happiness. Self-acceptance. One person wrote “Make life-long friends and live a great life to remember.” Two people took pictures of their hopes after they wrote them down. One man wrote that he wanted health for his brother – and the world. I don’t know this man or his brother, but we prayed together for his brother’s health, right there in the quad. I hope his brother is feeling better now.

Even those who couldn’t stop to answer my question smiled as they rushed by. Some people laughed as they were on their way to class, saying “No! I’ve got none left.” “Don’t worry about it,” I called after them. “You’re not the only one!” After awhile, I began including an additional offer: “If you don’t have any hope left, come absorb some of ours!” Hope, it turns out, can be contagious.

Like just about everyone else, I’ve been thinking a lot lately about contagion. In the last 18 months, many of us have learned far more about contagious diseases than we’d ever planned to. We know how vulnerable we are. We know how easy it is to transmit, carry, and catch a disease that quite literally takes your breath away. We understand, in a way that we’ve never understood before, that what’s inside of me touches what’s inside of you. That the health of one person can change the health of the world. We truly are all inter-breathing. And while that’s terrifying in the face of a pandemic, it also reminds me how intimately connected we are – by our breath, by our bodies, by the Oneness of the world.

This intimacy means we have the power to infect one another, to spread both physical and spiritual diseases. But that’s not the only option. My friend and mentor, Lee Kravetz, who is a marriage and family therapist, science journalist, and author in the Bay Area, wrote a book about social contagion, the spreading of behaviors, thoughts and emotions: “Whether it’s mirroring someone’s posture or mimicking someone else’s speech patterns, we are all driven by unconscious motivations triggered by our environment.” 

Social contagion theory teaches us that behaviors are infectious. Emotions are viral. Even thoughts are catch-able.  How we interact with individuals impacts not only how they interact with us – but also how they interact with others, with themselves, and with the world around them. We have the ability to influence others with something as minor as a smile, or eye contact, the colors we wear, the tone of our voice, the images we post on social media. And the most remarkable thing about them? Social contagion, like physical contagion, is often completely unconscious. We pick up on cues from the world around us all the time without even noticing what it was that shifted our mood or colored our experience. More important, I find, is that we are inadvertently influencing others’ thoughts, feelings, and behaviors, as well — and that includes positive cues, like hope, happiness, laughter, and benevolence. As we enter a new year – one in which we continue to fight another kind of contagion, I wonder what it would look like if we leaned into that power. How might we learn to spread the opposite of disease? Can we spread resilience instead? Or wonder? What would it look like to dedicate this year to spreading hope? 

Jewish sources include many examples of social contagion. Perhaps unsurprisingly, a lot of them are stories in which social contagion spreads for the worst – even in biblical times, bad ideas quickly went viral. Consider the story of the golden calf in the book of Exodus. The Israelites arrived at Mt. Sinai after many years of wandering in the desert, after God freed them from slavery. Moses went up the mountain to receive the Torah from God, and said that he would return in 40 days. The first emotion to spread was uncertainty. According to medieval commentator, Rashi, there was some confusion about the timing – would Moses come back on the sixteenth of Tammuz or the seventeenth? Did those 40 days include the day that Moses went up the mountain? When would Moses return? The next emotion that went viral was fear. Commentators disagree about who started spreading it, but soon, just about everyone was terrified that Moses would not return, believing instead that that God abandoned them to die in the desert. Some commentators say that Satan – yes, contrary to popular belief, Satan does appear in Jewish texts, but that’s a dvar for another day – Satan exacerbated the situation by showing the people an image of Moses, dead on the mountain, that was so real, the Israelites could reach out and touch it. 

Have you ever fallen into an anxiety spiral where the story in your head is more real than what’s in front of you? Did your fear come from a seed sewn by someone else? Many of us know what that feels like. 

You know what happens next – even Aaron, Moses’s brother, participated in building and worshipping a golden calf, a false idol. When social contagion spreads, it’s hard not to get swept up in the current. But not everyone does. Even in the story of the golden calf, the Torah noted that women refused to give their jewelry to Aaron to be melted down for the calf’s construction. And according to a midrash (a story about the Torah, which I like to call “Torah fanfiction”), the tribe of Levites also did not give in. The midrash also says that Miriam’s son, Chur, denounced those who were spreading fear – and he paid for it with his life. The angry and terrified crowd murdered him for standing up for what he believed in. It’s hard and sometimes dangerous to share a dissenting view when a social contagion is spreading. 

What about positive examples of social contagion from our tradition? Two took place at the Sea of Reeds, more commonly known as the Red Sea. A midrash teaches that when the Israelites stood before the Red Sea, with Pharaoh’s army behind them, one man took the first steps into the water. The man was given the name Nachshon, which comes from nachshol, “of the sea.” Nachshon faced the water, and the future, with bravery, and his courage was contagious. The others followed, and the sea split. 

After the Israelites made it to the other side and the army drowned in the waters behind them, Moses and Miriam each began to sing the song of the sea. Rashi says that Miriam thought to pack her timbrel as they were leaving Egypt because she believed so strongly in the coming redemption. When they began to sing, others joined Moses and Miriam in this joyful prayer of thanks to God.This is an example of a social contagion that started with one voice, and spread to many. And it’s a contagion of gratitude that spans the generations. This prayer is among the oldest lines of poetic verse in the Torah and they’re part of our daily liturgy. Mi Chamocha, ba’eilim Adonai? Who is like You, among the mighty, Adonai? 

A final moment to share, also from Exodus, takes place in the Torah portion we read the week after the incident with the golden calf. In Parshat Vayakhel, God tells the Israelites to build a mishkan, a sanctuary for God. “Everyone whose heart so moves him shall bring gifts for the Lord – gold, or silver, wool or linen, wood or oil, spices or stones, anything to make the Sanctuary more glorious for God,” said Moses. The Israelites, moved by their hearts, brought all kinds of golden objects, colorful wools, silver, copper, and acacia wood. They worked together to make the Sanctuary sacred for God. They eventually brought so many gifts that Moses had to ask them to stop. I love this contagion of giving. And I love the Israelites for how human they were. Of course they yearned deeply to give to the Holy One, to give so much that they had to be asked to stop – right after so many of them spread and gave in to the contagion of fear that led to the building of the golden calf. 

I’m sure many of us can think of contemporary social contagions, both negative and positive. Today I’m going to consider just one example from this summer. When celebrated Olympic gymnast, Simone Biles, decided to withdraw from the 2021 individual all-around competition to protect her mental health, her decision set a wave in motion. “I say put mental health first,” Biles said. “Because if you don’t, then you’re not going to enjoy your sport and you’re not going to succeed as much as you want to. So it’s OK sometimes to even sit out the big competitions to focus on yourself, because it shows how strong of a competitor and person that you really are — rather than just battle through it.” We’re just going to sit with that for a moment. Such a powerful statement about what matters most. Afterward, although a few commentators accused Biles of being a “quitter,” Biles’ decision to prioritize her mental health was generally widely praised and credited with starting a wider conversation about the role of mental health in sports. Other gymnasts relayed their own stories of struggle as a result of her sharing. Biles sent a message to all of us about the power of prioritizing health over performance. Before she withdrew from the competition, Twitter celebrated the gymnast’s excellence in her sport by creating a Simone Biles emoji that appeared whenever someone used the #SimoneBiles. After she withdrew, people continued to use that emoji, along with another hashtag: #mentalhealthfirst. Simone Biles taught us all that this is what excellence looks like. 

The ideas we share, the emotions we express, the stories we tell ourselves and others, all have the power to spread. Will we spread fear and distrust this year, building more false idols? Or will we spread something different, building a sanctuary of healing with our words, our hopes, and our actions? 

I want to clarify that I’m not encouraging anyone to spread toxic positivity – to “just be positive” in the face of suffering. Pretending that things are ok, when they’re not, is another form of idol worship at a time when the truth demands to be seen. Let’s be honest about the threats of our world, but let’s think about how we respond to them. One of my other mentors, Josh Feldman, says that “Our daily experiences are a laboratory for the invention of the future.” When we are in a lab, trying to create the next great invention, sometimes the experiment goes wrong. The data we collect from each experiment, even the failed ones, help us decide what to try next. We are not here to deny the darkness. We are not here to ignore the facts. We are here to decide what to do with them. 

What if the Israelites had approached their fear with curiosity and honesty while Moses was on the mountain? “Wow,” one might have said to the other. “I’m really scared right now. I’m not sure when Moses is coming back and I’m having a hard time trusting that we will be safe in the future.” That’s a truth worth sharing. “I’m afraid too,” the other might have responded. “Thank you for telling me. I’m grateful to know I’m not alone.” Vulnerable sharing, supporting one another, and speaking from your own experience, are also contagious behaviors. That might have been a better response to the facts of their fear.

The new year has begun and there’s still a lot of darkness around us. From the ongoing uncertainty of the coronavirus contagion to the horrific effects of climate change, gun violence, and systemic oppression.The pandemic taught us that the health of one person can change the health of the world. Social contagion theory teaches, and our Torah shows us, that the hope, courage, voice, and generosity of one person can change the world too. 

So I return to the question I posed at the beginning: What will you spread this year? How will you respond to the darkness? And how will you model what you want to see in your community when you show up as part of it? 

Anne Lammott writes, “Sometimes hope is a radical act, sometimes a quietly merciful response, sometimes a second wind, or just an increased awareness of goodness and beauty.” This year, spreading hope, wonder, or resilience may be a small act of bravery for you, an attempt to plot a better course, even when you feel the current pulling in another direction. Maybe it feels like a radical act, taking a bold step into the sea of your uncertainty, like Nachshon, or bringing the timbrel with you, like Miriam, because some part of you believes redemption is possible. Maybe you’ll put your mental health first and inspire others to do the same, like Simone Biles. Maybe yours will be the voice that encourages others to join the song. 

Two weeks ago, I stood on the quad and invited strangers to share their hopes with me. I’m going to conclude this part of our service by inviting you to do the same. What do you hope for this year? For yourself, for your community, and for the world – call it out. 

Thank you everyone. May we carry these hopes in our hearts and into the world, and may we be blessed with the courage to bring them to life. 

I ended this sermon with the song, “One Voice,” by the Wailin’ Jennys. I encourage you to listen to it now.