Emporos (ἔμπορος) is the merchant — literally "one who travels in" (from en + poros, passage). The merchant travels to buy cheap and sell dear, traversing distances and cultures. The word appears in Matthew's parable of the pearl and in Revelation's lament over Babylon.
The emporos in Matthew 13:45-46 is Jesus' model disciple: someone actively seeking, expertly assessing, and when he finds the surpassing pearl, liquidating everything else. This merchant knows value when he sees it. The same figure appears inverted in Revelation 18: merchants who grew rich from Babylon's corruption weep at her fall (18:11-15). They traded in everything including "souls" (18:13). The theological contrast: the good merchant trades earthly goods for eternal treasure; the worldly merchant trades eternal souls for earthly goods.
Ancient merchants were both admired and suspect — they crossed boundaries, knew prices, accumulated wealth, but were not rooted in community. Revelation weaponizes this ambivalence: Babylon's merchants are the epitome of rootless wealth-accumulation, crying as their profit-source burns. Against this, Jesus' merchant (Matt. 13:45) has the same mobility and market-savvy but applies them to the kingdom: he recognizes supreme value and acts decisively.