[Emily Dickinson's] dread of winter [is] expressed in one of her remarkable verses, written about 1861 [,"There's a certain Slant of light"]. It is, like the somewhat later "Further in Summer than the Birds," an attempt to give permanence through her art to the impermanent; to catch that fleeting moment of anxiety which, having passed, leaves the beholder changed. Such moods she could catch most readily in the changing seasons themselves. . . . /89/ Winter to her is at moments intolerably dreary, and she here re-creates the actual emotion implicit in the Persephone-Pluto myth. Will spring never come? Sometimes, winter afternoons, she perceives an atmospheric quality of light that is intensely oppressive. The colloquial expression "heft" is especially appropriate in suggesting a heavy weight, which she associates with the weight of great bells or the heavy sound that great bells create. This might be the depressing chill and quiet preceding a snowfall. Whatever it is, it puts the seal on wintriness. Coming as it does from heavens, it is an imperial affliction to be endured ("None may teach it—Any"). Even the landscape itself is depressed. When it leaves, she feels that whole body. The strong provincialism, 'Heft' (smoothed away to 'Weight' by former editors), carries both the meaning of ponderousness and the great effort of heaving in order to test it, according /216/ to her Lexicon. This homely word also clashes effectively with the grand ring of 'Cathedral Tunes,' those produced by carillon offering the richest possibilities of meaning. Since this music ‘oppresses,’ the connotation of funereal is added to the heavy resonance of all pealing bells. And since the double meaning of 'Heft' carries through, despair is likened to both the weight of these sounds on the spirit and the straining to lift the imponderable tonnage of cast bronze.
The religious note on which the prelude ends, 'Cathedral Tunes,' is echoed in the language of the central stanzas. In its ambiguousness 'Heavenly Hurt' could refer to the pain of paradisiac ecstasy, but more immediately this seems to be an adjective of agency, from heaven, rather than an attributive one. The hurt is inflicted from above, 'Sent us of the Air,' like the 'Slant of light' that is its antecedent. In this context that natural image takes on a new meaning, again with the aid of her Lexicon which gives only one meaning for 'slant' as a noun, 'an oblique reflection or gibe.' It is then a mocking light, like the heavenly hurt that comes from the sudden instinctive awareness of man's lot since the Fall, doomed to mortality and irremediable suffering. This is indeed despair, though not in the theological sense unless Redemption is denied also. As Gerard Manley Hopkins phrases it in 'Spring and Fall,' for the young life there coming to a similar realization, 'It is the blight man was born for.'
Because of this it is beyond human correction, 'None may teach it—Any .' Though it penetrates it leaves 'no scar' as an outward sign of healing, nor any internal wound that can be located and alleviated. What it leaves is 'internal difference,' the mark of all significant 'Meanings. ' When the psyche is once stricken with the pain of such knowledge it can never be the same again. The change is final and irrevocable, sealed. The Biblical sign by which God claims man for his own has been shown in the poems of heavenly bridal to be a 'Seal,' the ring by which the beloved is married into immortal life. But to be redeemed one must first be mortal, and be made conscious of one's mortality. The initial and overwhelming impact of this can lead to a state of hopelessness, unaware that the 'Seal Despair' might be the reverse side of the seal of ecstasy. So, when first stamped on the consciousness it is an 'affliction.' But it is also 'imperial . . . Sent us of the Air,' the heavenly kingdom where God sits enthroned, and from the same source can come Redemption, though not in this poem. /217/
By an easy transition from one insubstantial image to another, 'Air' back to 'a certain Slant of light,' the concluding stanza returns to the surface level of the winter afternoon. As the sun drops toward the horizon just before setting, 'the Landscape listens' in apprehension that the very light which makes it exist as a landscape is about to be extinguished; 'Shadows,' which are about to run out to infinity in length and merge with each other in breadth until all is shadow, 'hold their breath.' This is the effect created by the slanting light 'When it comes.' Of course no such things happen in nature, and it would be pathetic fallacy to pretend they did. The light does not inflict this suffering nor is the landscape the victim. Instead, these are just images of despair. /218/
From Emily Dickinson: An Interpretive Biography (Cambridge, Mass.: The Belknap Press of Harvard University, 1955), pp. 189-190.