Anne Brontë's poem is one long sentence of discomfort that finally comes to rest on a single fact. Its speaker is out in the world and cold in every sense, and what she holds onto is the knowledge that somewhere a home exists. The central idea is that being known and welcomed is a kind of warmth. Simply knowing such a place exists, even from far off, can be enough to keep despair away.
The poem is built on concession. The first stanza piles up the bleakness, with its woods, damp ground, leaves and wind, before the main clause arrives: "There is a friendly roof, I know." The next stanzas repeat the move at greater length. "Though" opens three times, "When" follows, and only then does the pivot come: "I know there is, though far away, / A home where heart and soul may rest." Holding back the main statement for so many lines makes the relief feel earned, like a door closing on the weather. "I know" appears twice, and the confidence grows between them. In the first stanza the roof "might shield" her, but by the fifth the home simply is.
The form is plain and steady. The lines are mostly eight-syllable iambics ("Though BLEAK these WOODS, and DAMP the GROUND"), and every quatrain rhymes ABAB. The effect is hymn-like, close to the rhythm of someone walking steadily on. The one rhyme that doesn't quite fit is "long" with "tongue", which is only approximate. That might suit a stanza about solitude silencing the speaker, though that is my reading rather than something the poem states.
Temperature is the main pattern in the imagery. The outdoor cold comes first: damp ground, "fallen leaves so thickly strown," and a wind with a "wild and melancholy moan." The wind has the only voice in the landscape, which hints at how few people speak to her. Then the cold moves inside. The word returns in "Cold stranger-glances," and "stranger" comes back when solitude "makes mirth a stranger to my tongue." Eventually the cold settles as "ice that gathers round my heart." Against all this stand the "ruddy glow" of the fire, the "Warm hands" and the "warmer heart." That warmth is honest, too. It "will not belie" itself, unlike the glances that slide past her, and the "smiling lip and earnest eye" at home answer the "stranger-glances" that meet her eye in the world.
Some of the best details are small. "Unheeded swells the unbidden sigh" gives a sigh she never meant to make and nobody notices. Kindly thoughts "flow back discouraged to my breast," and a few stanzas later the ice is "thawed." Both images treat feeling as water, which can be turned back, frozen or released. Home is what lets it run again.
Time matters as well. Solitude makes "youthful joys too soon decay" and "overclouds my noon of day," so youth is already shadowed at its brightest hour. The promise of home is therefore partly a promise of recovery: the joys "that now depart / Will come to cheer my soul again."
The ending is the poem's only exclamation: "My heart shall never know despair!" Yet the sentence begins "While such a home remains to me," and that condition keeps the hope from being naive. The comfort depends on something that could be lost, and the speaker seems to know it. By now home has also become portable. It is "that thought" that will be her "hope, my comfort, everywhere," so the place is carried in the mind. The title, "Lines Written From Home," seems to point the same way, since the poem speaks as if home is still with her even while she is away. That is an inference from the text, not a known fact about its writing.
The poem is significant for how modestly it works. Anne Brontë, one of the three Brontë sisters, makes loneliness concrete without melodrama, using ordinary words like damp, cold, warm and home. Its consolation is real but measured. It doesn't claim the world will turn kind, only that one warm place is enough to keep the speaker steady while she walks through the cold.