This poem paints a vivid and stark portrait of winter, not just as a season of the year, but as a metaphor for human mortality, struggle, and the inexorable passage of time. Here's a breakdown of its themes and imagery:

1. The park as a symbol of desolation:

• "The park is winter-plucked. The sky / and the grey pavement show a sheeted face"
  Winter strips life from the park, leaving it barren and lifeless. The "sheeted face" evokes an image of death, as a sheet often covers a corpse, symbolizing the inevitability of mortality. The park's lifelessness mirrors the "covered stare of one who had to die," emphasizing the universality of death and the silence it imposes.

2. Human labor and futility:

• "Now, when men sweat, / shoveling muddy snow or heaving ice, / they know the helpless sweat that will not wet them twice"
  The act of labor—shoveling snow, a repetitive and seemingly endless task—is likened to life's struggles. The "helpless sweat" suggests that these efforts are ultimately futile in the grand scheme of life and death, as they do not yield enduring results. The line captures the fragility and impermanence of human exertion.

• "They know the staggering heart, the smothered breath / that stand between this knowing and the end"
  This describes the physical toll of both labor and existential awareness. The "staggering heart" and "smothered breath" reflect the proximity of life's limits—the bodily reminders of mortality.

3. The heaviness of time:

• "Though they must drag a net of heavy hours / about their straining limbs"
  Time is depicted as a burdensome net that traps and weighs individuals down, making their struggles even more arduous. Yet, this burden is finite—it will eventually "break" as time runs out.

4. Transience of love and faith:

• "Love like a pillar of cloud, a pillar of fire— / this net will break before they tire, / this cloud, this flame will vanish and be cold"
  The reference to the "pillar of cloud" and "pillar of fire" draws from the biblical Exodus story, where God guided the Israelites through the wilderness. Here, it suggests love or faith as a guiding force in life. However, the poet warns that these too are transient, destined to "vanish and be cold," leaving behind only emptiness.

5. The unyielding return of winter and mortality:

• "Winter is on us now, and will return: / soiled snows will choke the city streets again"
  Winter, a cyclical season, becomes a metaphor for death and hardship, which also recur endlessly. The "soiled snows" evoke decay and corruption, suggesting that life's struggles and losses are inevitable and will always resurface.

• "Bleak twilights dull the windows as before, / dark hurrying crowds push towards lit rooms in vain"
  The imagery of "bleak twilights" and "dark hurrying crowds" captures the futility of human attempts to escape the cold, literal and metaphorical. The "lit rooms" promise warmth and comfort, yet the attempt to reach them is described as "in vain," emphasizing existential despair.

6. The finality of life:

• "One day we shall not kiss or quarrel any more"
  The poem concludes with an acknowledgment of life's ultimate endpoint. The simple acts of love and conflict—hallmarks of human connection—will cease, leaving only silence.