I’m shocked that nobody has mentioned Shakespeare yet. Maybe because they’re technically plays…?
Older than that, Catullus 101 is stunning. Short little poem that has huge impact, even thousands of years later. Hail and farewell really sticks with you.
Rilke. Rilke every time. “Letters to a Young Poet” is truly fantastic, and should be required reading for any person who loves another person, but I keep arriving back at the beginning of his “Fragment of an Elegy”
“Now shall I praise the cities, those long-surviving (I watched them in awe) great constellations of earth. For only in praising is my heart still mine, so violently do I know the world. And even my most bitter lament turns into a paean before my disconsolate heart.”