Yu, Very insightful comments!
Everything Bach wrote was a prayer. He was a genius and a Lutheran, an inch wide and a mile deep. More focused and profound than simple, I would say.
Beethoven- He had a soul as large as Bach, and his early tutor was a Lutheran and disciple of Bach. But Beethoven did not share Bach's certainty, and instead asked divine questions in very human terms.
Brahms-Yes, after all this life long bachelor's motto was frei aber einsam. Free but alone.
Schubert's music at its best sings with a lyricism that would make even Mozart envious.
Bruckner= I always think of him as the Roman Catholic Bach. I would say the same of him as Bach. Everything Bruckner wrote was a prayer. The character of his music as compared to Bach reflects not only the difference in time but also the difference in theology. However, for a different Bruckner, please try Venzago's Bruckner 2. All I can say is wow! Mario Venzago is on to something.
Mozart-The singer of love and Mahler, the singer of nature, to quote Franz Welser-Most.
Now Chopin? Though I now love his music, it has not provided a window into his soul. For that reason, he will never be as dear to me as Bach or Bruckner, though his music brings me deep satisfaction.