Having learned what the Church teaches about the Trinity, now we turn back to St. Thomas Aquinas for help understanding that teaching. Aquinas will offer us a theoretical model for thinking about the Trinity, and our task will be to test his model against both the magisterium and Scripture. A good model should not only be compatible with the sources, but should predict both what they say and how they say it.
In just under 15 minutes, I talk through what we should expect from such theoretical models, and how we can and can’t “prove” the Trinity from reason. I also point out a translation error in our text–my fault, since I was supposed to correct the text last year. But as always, you can get the very latest version of the text at aquinas.cc. Right-click here to download the lecture, or listen using the audio player below.