introduces the setting of the poem: it is dark and there is snow on the ground. Thomas provides the beautiful image of a doe and fawns: the word "fallow" here means "of a light yellowish-brown color." The sense the author gives us in the first stanza is that out in the dark of a cold winter night, the fallow fawns and doe (of the same color—are they related?) are invisible in the night, as the wind blows fiercely—the wind is moving as fast as the stars move slowly.

Out in the dark over the snow
The fallow fawns invisible go
With the fallow doe...

In the second stanza, the author describes that the darkness moves in a stealthy and haunting way, which may account for his fear when the lamp suddenly goes out. It seems that he is saying that the darkness moves more swiftly that the fastest dog, when the light is extinquished…he personifies the darkness, saying that it "arrives" and all else is covered by it, or "drowned."

Stealthily the dark haunts round
And, when a lamp goes, without sound
At a swifter bound
Than the swiftest hound,
Arrives...

All sharing the dark now—the star, the speaker, the wind and the deer—they are bound by the darkness: this they all have in common.

And star and I and wind and deer
Are in the dark together...

And while some of them may be near—either literally by location or because they are all sharing the experience of complete darkness— certain things separate them. The star is actually very far away and, in fear, the animals may have picked up the speaker's scent on the wind. The dark they may have in common, but they are all very different, and in the darkness, the speaker admits to fear that "drums on my ear," even though he is in the "sage" or wise company of a celestial body, beautiful animals of nature and the wind—the company is "drear" perhaps because of the darkness or the winter cold, or both.

The last stanza presents a challenge. It seems that within the universe of things that can be seen, light may seem sometimes weak and little—perhaps this refers to how the world can sometimes seem like a dark place—maybe when worries or problems overwhelm us. Love and delight may not be able to stand up against things of might, and perhaps this refers to war, or power, that often takes little note of the sweeter aspects of life. At the same time, the first and last line of the final stanza may be tied together, as the lines in between are all separated by commas—like a list. Perhaps it makes more sense to read:

How weak and little is the light…
If you love it not, of night.

This may mean that if you do not love the night and the darkness, the light may seem weak and little, especially if you are afraid.