Context

"Goblin Market" (1862) follows two sisters, Laura and Lizzie, beset at twilight by goblin merchants hawking luscious, otherworldly fruit. The cry "Come buy, come buy" is the goblins' sales-call, returning as a refrain through the opening, and it is the lure to which Laura succumbs, trading a lock of her golden hair for a taste that leaves her wasting with insatiable craving.

How the repetition works

Phrasal repetition — a multi-word unit repeated adjacently, functioning more like refrain or incantation than single-word emphasis. About this distinction →

Where every other entry in this catalogue uses epizeuxis to register an inner state, Rossetti's is its first example of the device as commercial enticement: the doubled "Come buy" is a hawker's street-cry whose repetition is the rhythm of sales-patter, built to wear down resistance rather than to express feeling. Because the repeated unit is a two-word phrase, it reads as phrasal epizeuxis, and its recurrence as a refrain turns the seller's pitch into the poem's hypnotic pulse, so that the repetition itself becomes the mechanism of temptation.