«In loving thee thou know’st I am forsworn,
But thou art twice forsworn, to me love swearing».
The end of the relationship between the poet and the woman becomes apparent. Addressing the woman with a sense of shame and outrage, the poet is fully conscious of his own adultery and that of his mistress, as well as her infidelity to him and his lack of moral perception: “In loving thee thou know’st I am forsworn, / But thou art twice forsworn.” A reconciliation between the poet and the woman is suggested, but subsequently the poet accuses her of “vowing new hate after new love bearing.”
In loving thee thou know’st I am forsworn,
Sonnet 152 summarizes much of the poet’s past feelings and actions concerning the woman. Self-pityingly he cries, “I am perjured most,” and then follows this claim with a litany of how the woman has forsaken all of his oaths to her. In a rare act of perception, he acknowledges just how blind love has made him: “And, to enlighten thee, gave eyes to blindness, / Or made them swear against the thing they see.”
The concluding couplet emphasizes the irony of the woman’s dark appearance, which in previous sonnets the poet characterized as fair, and of her fair character, which he now realizes is metaphorically dark, or immoral: “For I have sworn thee fair: more perjured I, / To swear against the truth so foul a lie!” Some editions read, “more perjured eye,” with a pun on “I”; others read, “more perjured I,” which echoes the phrase “I am perjured most” from line 6. However, whether the phrase is correctly conveyed with “I” or “eye” is relatively inconsequential: The poet and his “eye” have been inseparable throughout the sonnets, and both are unable to perceive reality using reason rather than passion.
English audio from YouTube Channel Socratica
Summary from Cliffsnotes.com