When I arrived in front of St. John's Episcopal Church in Lafayette Square on Monday, June 1, bringing granola bars and cases of water, the mood was upbeat. I couldn't have imagined the grotesque scene that would unfold hours later — that the police would shove us out of the way with riot shields, pepper balls and smoke canisters, to clear a path for President Donald Trump.

It was 4 p.m. by the time I got to the church. People were milling about the St. John's patio: 20 to 30 protesters who sat on the steps, or drank some water, watching the action across the street, and 20 clergy and parishioners from churches around the city. Our plan was to be there until 6:30 p.m., offering peaceful, prayerful support. A team from Black Lives Matter had set up a first aid area, with boxes of bandages and first aid supplies and bottles of eyewash.

Demonstrators packed H street, Lafayette Square and the end of 16th street. Heading north up 16th, they were scattered in clumps and pairs, carrying signs and chanting: "Say his name: George Floyd!" It wasn't quiet — you could hear cheers from the protests — but it was peaceful. My colleagues and I passed out water and snacks. People exchanged prayers and elbow bumps. Things were so calm that, by 6 p.m., most of my colleagues had left. I decided to stay until I could no longer be useful; so did my church's seminarian, Julia, who is also a trauma nurse. The BLM medical folks taught me how to do an eye wash and gave me medical gloves. We waited, hopeful our services wouldn't be needed.

The curfew wasn't due to take effect until 7 p.m. But around 6:15 p.m., everything shifted. The crowd grew tense as police started to move out of the park. Trails of smoke come from Lafayette Square, followed by clouds of acrid smoke billowing through the crowds. People began to run north on 16th street and onto the St. John's patio, some coming for eyewash, wet paper towels or water. The first flash grenade rang out, sounding like gunfire, and some people dropped to the ground, thinking that the police were shooting.

People ran toward us and there was yelling and panic. We called out, "Water! Eyewash!" Julia and I were washing out protesters' eyes and feeling it ourselves. I was coughing; Julia's eyes were red, swollen and tearing. There was a shout that someone was hurt, and Julia ran to help. When she came back, she told me that she had seen police on horseback approaching. The seminary team decided it was time to leave.

Minutes later, the intensity of the flash grenades and gas clouds increased as the police began pushing protesters out of the park and onto H Street. More people ran in our direction, crying from the smoke and from fear. Someone yelled "rubber bullets," and I looked up from washing someone's eyes to see a man holding his stomach, bent over. He moved his arms, and I saw marks on his shirt. When I looked over his shoulder, I couldn't believe my eyes. A wall of police in full riot gear was physically pushing people off the St. John's patio, maybe 15 feet away from me.

The BLM team, far more experienced than I, said we've got to go. They picked up what they could of the medical supplies and quickly dropped back, around 30 feet to the north. I was so stunned, all I grabbed was a few water bottles. I was still clutching my bottle of eyewash, and I rushed to join the medical volunteers. What was happening? It's not even 7 p.m., I thought. Why were they doing this?

I walked through the crowds — "Water? Eyewash?" — and bent over folks, washing eyes or pouring solution on paper towels or handkerchiefs. We got pushed back again. We had not intended to be on the front lines, but the police had literally pushed the front line across the park, then H street, then the patio of St. John's. More flashes, more smoke, more panic. I ran out of water and found the BLM medical staff at K street, which was now the "back of the line." I gave them the rest of my eyewash bottle. I was scared. I had had enough. They were so brave.

As I walked to where I'd parked, I could still hear occasional bangs. I peeled off the two layers of blue medical gloves and put them in my pocket to throw away later. My phone started to ping. In their messages, colleagues, friends and family asked where I was and whether the president was really going to speak in front of St. John's. No way, I replied. It's crazy out here. I can still hear it. I got to the car. My sister texted, Gini, they're showing him on the news right now, walking across the park!

I drove home. Then Julia texted me: Did we really just get gassed for a PHOTO OP? My revulsion was immediate and strong, the reality of what happened sinking in: The president had used military-grade force against peaceful protesters so he could pose with a Bible in front of the church. I sat in my driveway and wept.

There were so many layers of irony and hypocrisy. People were protesting the fact that their government had been enslaving, incarcerating, overlooking and brutalizing them for generations — and the government brutalized them again. Religious people, who were literally wiping away the protesters' tears, were driven off the church property with brute force and fear. All so that Trump could use the church as a backdrop and wave the Bible like a prop. It was beyond offensive. It was sacrilege.

Monday night, I couldn't sleep.

Finally, it was a new day. I asked myself: How can I be a force for goodness today? How can I become a force to be reckoned with?

And so on Tuesday afternoon, I returned to the square.

Gini Gerbasi is the Rector of St. John's Episcopal Church in Georgetown. She is a 2007 graduate of Wesley Theological Seminary and has both a BA and JD from William and Mary.