When I lived near the Art Museum and attended services regularly at the Cathedral Basilica of SS. Peter and Paul, I sometimes noticed people doing odd things.

There were times when I felt vaguely threatened by aggressive panhandlers near the church steps or uneasy going to my car after dark. Inside, surrounded by so many other worshipers, I always felt safe.

So, to see a woman attacked during an 11 a.m. Mass on Sunday was more than a little unnerving. Each time I watch the video of that ugly incident, I get triggered all over again.

It actually makes me shake with anger. The nerve of someone to walk into a church, of all places, and sucker punch a female lector in the face like that, and then stroll off as if the assault had not taken place. I can’t stand a bully. The assailant’s target was considerably smaller and clearly caught off guard.

The brief encounter was caught on a Facebook livestream.

It happened shortly after the first and second readings. The lectors had just bowed in front of the altar, then turned and headed in the direction of the pews. As they approached the communion rail, an assailant dressed in a green track suit and a face mask was waiting. Once one got within arm’s reach, the assailant jabbed the lector closest to her not once, but twice in the face before yelling something unintelligible.

That lector is a better woman than I, because instead of swinging back, she merely continued walking back to her seat. She was a walking example of God’s grace in action. That lector managed to stay at least outwardly calm, and the priest continued with the Mass as if nothing had happened. Many worshipers probably weren’t even aware that it had.

CBS3 identified the victim as Sarah Contrucci, who told them the assailant had mumbled “something about respecting God.”

“I saw somebody there that clearly seemed to be waiting there, and I was a little worried that she was going to attempt to make a scene of some sort, to disrupt the Mass,” Contrucci told reporter Joe Holden. “So I was thinking that I wanted to do whatever I could to keep the situation calm and respectful, and so I just wanted to get back to my pew and allow the Mass to resume.”

She wasn’t injured. The assailant, whom the lector didn’t know, was reportedly in custody late Sunday but no charges had been filed as of Monday.

Archdiocesan spokesperson Kenneth A. Gavin said, “Such behavior is unacceptable at all times, especially within the confines of a church building and during the celebration of the holy Mass. We regret that this incident took place.”

Considering all of the bloodshed that took place in the streets of Philly over this weekend, this is minor.

The incident caught my attention because it happened inside a church — not to mention a cathedral. It was captured on video and is an ugly example of how quickly a situation can turn from peaceful to violent. You don’t have to do anything to trigger it. Someone can be emotionally unstable and the next thing you know, they’re unleashing on you.

Because the assailant was Black and the victim white, you can imagine the ugly racial comments that have been made on social media about the incident. I’m proud, though, that I saw none of that stereotyping on Archbishop Nelson Pérez’s Facebook wall, where he called the assault “a senseless act of aggression.”

I really hope the cathedral doesn’t respond to this aberration by installing a bunch of uniformed guards.

The beauty of the church is that it’s a welcoming place where those who have nowhere else to go can come inside and worship with no questions asked.

I would hate for that to change.