There have been moments in my life when the concept of "harmony" transcended the philosophical. That unique experience of having the physical and the metaphorical coalesce. Singing in a choir can do that. The choir doesn't have to be professional, it doesn't even have to be very good in general. But, for that one brief moment, everything comes together and the sounds lift you to another place. The exact dates don't really matter - a couple of times in high school, singing in a small choir in Victoria, the Glee Club in Ithaca, conducting a piece I composed with the cantorial school choir. When the notes are in tune, and the understanding of the piece is aligned, the music can resonate.
It takes work to bring a choir, and a piece of music to the point of resonance. There must be a level of trust and understanding that isn't accidental. In a choir, that work is conscious, but the same work is required in any team aspiring to reach another place. A team. A congregation. Trying to resonate.