The speaker feels that his feet are "honored" by the "heavenly socks" that were knitted for him by a shepherd. They are as "soft / as rabbits," and they make him imagine that his feet have been transformed into all manner of things: fish, sharks, blackbirds, cannons. It is as though the colors—the violet and the sea-blue, and a golden thread—are transformative. In fact, the socks are so beautiful, he says,

for the first time
my feet seemed to me
unacceptable
like two decrepit
firemen, firemen
unworthy
of that woven
fire . . .

In other words, the socks are so gorgeous and wonderful that he feels that his feet are actually unworthy of them—that his feet are too ugly for their beauty. He has to resist the urge to save them, and so he puts them on with gratitude and reverence and awe. He even compares them to beautiful birds that are worthy of a golden cage and "pink melon" to eat. He even feels somewhat "remorse[ful]" about pulling the socks onto his feet, going back to the idea that he feels somewhat unworthy of their beauty and goodness.

The speaker feels grateful and special due to the gift of affection.

The speaker’s feelings are well-represented in the last lines.

The moral of my ode is this:
beauty is twice beauty
and what is good is doubly good
when it is a matter of two socks
made of wool in winter. 

He appreciates the workmanship put into the socks.  Like the poem, the socks are a simple way to show caring.  He appreciates them, and the person who made them for him.  Mara Mori is special to him, and shows that he is special to her by making him the socks. He resists the urge to shelter this special relationship, and instead lets it breathe and lead a natural life.

We can’t hide away things we value.  We need to live with them and appreciate them, whether they be special socks or special people.