Funny you wrote this. I had a similar experience this past weekend at a church I was speaking at. It's a plant by one of my friends in an impoverished city. Half of the church stood out on the street smoking before the service it seemed, but they were out in the neighborhood talking to people, inviting them in, etc. 

After I shared the sermon they did a series of worship songs that really kept the focus on Christ. They invited the kids out of the nursery and gave each of them an instrument. It was pretty chaotic, but something happened in that moment where I sensed God was pleased. I felt that it almost didn't matter what we did next in the service because we were connected with God. I'm not doing the moment justice, but it felt a bit like what your friend described.