Bach on Trinity Sunday
Back when my time in churches was spent on an organ bench, I used to play this sometimes on Trinity Sunday. There’s no actual connection between Bach’s präludium and the Holy Trinity, just a proliferation of threes and the sublime scope of the piece. (My performances tended toward a Schweitzer tempo, but this one is a masterful and zippy performance.)
If you want some “real” Trinity music, check out this Bach cantata, some music by Messiaen, or perhaps this Festival Te Deum of Britten. If you want an old-fashioned CD for the occasion, this is your buddy.