According to today's homily, St. Augustine was told that by an angel that it would be easier for a human to dig a hole and fill it with the water of the ocean than to understand the Mystery of the Trinity. I'm not going to doubt such an interesting analogy; there are certainly elements of our universe that we simply cannot comprehend. Yet I prefer to think of the Trinity, though I might not understand the entire Mystery, as something a little closer to human comprehension.
Take Saint Patrick's idea of the Shamrock: three leaves, yet one plant. Or better yet, I like the analogy made by a Christian comedian (whose name currently escapes me) who said that the Trinity was like a fresh, homemade cherry pie cut into three pieces. On the surface, they look like three pieces, but underneath the crust it's still one pie with filling interconnecting what looks like separate pieces.
I may have said this before, but I think that we, as creations in the image of God, might not fully understand the Mystery of the Trinity, but we deal with it within ourselves on a daily basis. We, too, are divided into body, mind, and soul. We, too, sometimes talk to ourselves yet recognize that we are still one person (well, many of us do ...).
What I really liked about today's homily was the emphasis that, although there is only one God, He is not alone. His very essence (the Trinity) is a being of love, which is why when He revealed Himself in the form of His Son, the message was a message of love: "Love one another as I have loved you."
... Now I want some pie ...