It’s called the Athanasian Creed, by the way.
I had never read this until you posted it. God bless you for this!
Really? I thought you would have. I discovered it a few months ago on Quicumque Sunday. We chanted it in procession around the nave. It really made an impression on me, and the more I look at it the more I become impressed with its clear, cogent declaration of the faith. It was obviously written (about 600 I think) to address certain heresies, Arianism, Nestorianism, and Gnosticism to name a few.