The speaker begins by admitting he is forsworn—he has broken faith. He then points out his beloved is twice forsworn: she broke her marriage vow and later broke new promises of love. But instantly he questions why he blames her for two lies when he himself breaks twenty. He has made oaths about her deep kindness, love, truth, and constancy, even though he knows these oaths are hollow. He has willfully blinded his eyes or forced them to swear against what they plainly see. In the closing couplet, he confesses the deepest lie: he swore she was beautiful. That makes him the greater perjurer, because he knowingly told a foul lie against the truth. The speaker’s mood is weary and bitterly self-aware. There is guilt, but also a sharp irony—he is trapped in his own self-deception, and his accusation of her only exposes his own willing blindness.
Sonnet 152: In loving thee thou know'st I am forsworn — Summary
In loving thee thou know'st I am forsworn, But thou art twice forsworn, to me love swearing; In act thy bed-vow broke, and new faith torn, In vowing new hate after new love bearing: But why of two oaths' breach do I accuse thee, When I break twenty? I am perjur'd most; For all my vows are oaths but to misuse thee, And all my honest faith in thee is lost: For I have sworn deep oaths of thy deep kindness, Oaths of thy love, thy truth, thy constancy; And, to enlighten thee, gave eyes to blindness, Or made them swear against the thing they see; For I have sworn thee fair; more perjur'd I, To swear against the truth so foul a lie!