The speaker addresses a lover he once parted from, and now sees again—but everything has changed. Their reunion isn’t what it was; both hearts are heavy, full of doubt and unspoken feeling. He looks back on a single, intense moment that bound them, a flash of joy that vanished as quickly as lightning, a snowflake on a river, or a sunbeam swallowed by shadow. That instant was singled out from time and became the start of a life of pain, its sweetness a beautiful delusion that can never return.
He confesses that if she had known how completely she crushed his heart, she might have let him die—perhaps in her tears, that ‘briny dew’. The final lines ache with the irony: the cost for that brief, lost moment seems far too small for the suffering it brought. The poem creates a mood of fragile regret, a quiet bitterness over a joy that proved too fleeting and too costly.