The speaker begins with a blunt admission: they are let down by both God and authority. The two are named in the same breath, as if they were equally empty. Yet the second stanza turns on a surprising "yet." Even so, the speaker finds it "so necessary" to have something greater than themselves. The need hasn't gone away just because the old answers failed.
The last stanza suggests where that greater thing might be found. Sand, sea, and "every foot of this road" are physical and close at hand. Judging by the title, the speaker is a wanderer, and the poem seems to place meaning in the landscape rather than in religion or rulers.
The mood is quiet and restless at once. There is some bitterness at the start, but it settles into something humble and open. The short lines and lack of punctuation feel like walking: one step, then another, and the world slowly taking the place of belief.