The speaker describes a mountain scene full of contrasts: bright, lively streams, heavy shadows, tall trembling trees, and a faint wind that seems to come from far-off seas. At first the landscape feels real and physical, but then it shifts. The light, the sound of water, the shadows, and the calm air start to feel like dreams or distant echoes rather than solid things.
There is a hushed, reverent, slightly eerie mood throughout. The mountains are called holy, yet the poem ends with “inconceivable dark seas,” as if the visible world is only a thin veil over something vast and unknowable. The speaker seems moved and a little unsettled, sensing that what can be seen and heard is only a faint trace of deeper, hidden worlds.