In the final part of “Lines Composed a Few Miles Above Tintern Abbey”, Wordsworth turns to his sister, Dorothy Wordsworth, and says that through her, he can relive his own youthful experience of nature.
He sees in her the same excitement and wonder he once had as a younger man:
“...in thy voice I catch
The language of my former heart, and read
My former pleasures in the shooting lights
Of thy wild eyes.”
These lines clearly show that through her voice and eyes, he reconnects with his past self and youthful joy.