It appears in his poem "The Clod and the Pebble", written in 1794.
The poem explores the contrasting views of love, one based on earthly passion and the other on divine love. The speaker, a clod of clay, expresses his longing for the pebble, which is seen as a symbol of the divine. The pebble responds with the famous line: "Love seeketh not itself to please, / Nor for itself hath any care, / But for the glory of the Maker / It seeketh only to endure."
Blake's quote highlights the awe-inspiring power of nature and the limitations of human creativity compared to the divine.