The speaker recalls a sorrowful walk he took the evening before, a path he thinks he’ll come to regret. On that journey, he received a mortal wound — not from a blade, but from a pair of sweet, lovely blue eyes. He runs through her other beauties: bright golden curls, lips like dewy roses, a lily-white breast. Yet none of that is what undid him. It was only her eyes.
In the second stanza, she talks and smiles, beguiling his heart without him knowing how. Each sharp pang, each deathly blow, comes straight from those bonnie blue eyes. A folk proverb tells him that keeping quiet wins nothing, so he’ll speak up and hope she listens to his vow. If she refuses, he says, he’ll simply lie down his dead body at the feet of those same eyes. The feeling is tender and a little theatrical — a mood of dreamy helplessness, where love feels like a beautiful, fatal blow.