Setting: Neruda gives only a few clues about the setting of this poem.
In the beginning of the poem, the speaker tells us that a friend gave him a pair of socks that she had "knitted herself /with her sheepherder's hands." This could indicate that the poem is set in Neruda's homeland of Chile, S.A., where sheepherding is an important industry.
At the end of the poem, the speaker praises the value of "two socks / made of wool in winter." So, we know that the action of the poem takes place in the winter.
The most important image is, of course, the socks themselves. They are described as:
"soft as rabbits";
The speaker uses several images to explain that he does not want to store away the socks like a museum piece:
He does not want to "save them somewhere as schoolboys / keep fireflies, / as learned men collect sacred texts." In both these images, a precious object is kept for observation but is not really used, the way the speaker wants to use his socks.
Theme: To me, the theme of the poem is that a thing of beauty can be best appreciated by using it. The poem concludes:
beauty is twice beauty
and what is good is doubly good
when it is a matter of two socks
made of wool in winter.
The speaker seems to be saying that the socks--when used properly, as coverings for the feet--have a double beauty: their beauty as something to be observed, and their beauty as something to be used.