The Trinity Shield
Church of the Assumption, Windsor, Ontario, Canada
The circle in the center has the word Deus, "God." The three outer circles are labeled Pater, Filius, and Spiritus, "Father," "Son," and "Holy Ghost." Each connects to the "God" circle by means of a white ribbon with the word est, "is." In other words, each of the three "is" God. At the same time, the ribbons connecting the three to each other bear the words non est, "is not." That is, the Father is not the Son and is not the Holy Ghost; the Son is not the Father and is not the Holy Ghost; and the Holy Ghost – well, you get the idea.
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More of the Trinity
Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license. Date provided by Delcol.