I am not about to convince you that reading Rainer Maria Rilke can change your life, though it might. Of course, you have to understand his poems, which can be quite a challenge because it really means understanding the German originals. Even in the various good English translations, I find complexities and would find teaching them impossible (in a way that teaching Dante is not).
Yet I have always sensed a mysterious power in his taut verse, which searches for the ineffable in a pre-modernist mode--he died in 1926--that speaks to the secular world of the early 20th century about matters of the spirit.
Although most people who read them admire his Duino Elegies and Sonnets to Orpheus, I have a devotion, thanks to Robert Bly's translation, to his earlier Book of Hours, or, as Bly calls it, A Book for the Hours of Prayer. This was Rilke's first major book, written 1899-1903.
Here Rilke shows himself to be the poet of solitude and silence, the poet of darkness, the darkness of fertility and unknowing, as in the mystics of the medieval tradition. Although Rilke rejected the smothering piety of his mother's Catholicism, he was deeply affected by its traditions and by the value of prayer, especially the via negativa.
Rilke is the poet of inner spaces, as if interiorizing the desert image found in other writers. He is also the poet's poet, the careful craftsman who lived largely in isolation in various parts of Europe, waiting for the great outbursts of inspiration that produced both lyrical prose and incomparable verse. Although he can be faulted for seeming self-centered, Rilke speaks with a cosmic voice, as when he says (Bly's trans.), "I have faith in nights."
This poem begins by addressing God or the creative darkness: "You darkness that I come from,/I love you more than all the fires/ that fence in the world...it is possible a great energy/ is moving near me." You see what I mean: the English is uniquely direct, simple in style, yet subjective, elusive and untranslatable. He is like a modern John of the Cross. (I am reminded of T. S. Eliot's statement that we do not have to understand a poem in order to appreciate it.)
The holy in these poems is deep down within, dark and distant yet always close, too, beyond time and place. Bly says that Rilke's final sonnets are essentially poems of praise, so we have poetic prayers of appreciation and longing in verse that is religious despite its rejection of religion in the usual sense.
From his prose, I must quote some memorable lines from his "Letters to a Young Poet":
"Be patient with all that is unresolved in your heart. Try to love the questions themselves. Do not seek answers which cannot be given to you now because you would not be able to live them now. And the point is to live everything, to live the question now."
And: "Believe in a love that is being stored up for you like an inheritance and have faith that in this love there is a strength and a blessing so large that you can travel as far as you wish without ever having to step outside it."