A symbol for today

This symbol is at the apex of two of the east windows in Holy Trinity Dunoon. It's fascinated me ever since I discovered that there is writing on it - because without the photographic fiddling of swiftmidges you can't actually make out more than a few blurred shapes when you're sitting in the pew. 

For the uninitiated, it's a symbol summing up the doctrine of the Holy Trinity. Deus (God) is in the centre roundel, with Pater (father), Filius (son) and Spiritus (spirit) in the three placed round the perimeter. The legs leading from Deus to the other three contain the word Est (is), and the periphery contains, in each segment, Non Est (is not). 

It's been part of my life for the past 43 years now, something I was wont to doodle on my papers at Provincial Synod meetings back in the day when it was new and fascinating. Today I was preaching, and that shape gave me my lead in.

And for the very first time in my life we recited the Athanasian Creed. Now there's a thing ...