«Love is too young to know what conscience is;
Yet who knows not conscience is born of love?».
If the poet ever hoped that his soul would win out over his body, as he does in Sonnet 146, and that his reason would return to govern his senses, he was sadly mistaken.
Love is too young to know what conscience is;
In Sonnet 151, his body’s lust for the woman completely controls his actions and thoughts. Resignedly he admits to the woman, “For, thou betraying me, I do betray / My nobler part [his soul] to my gross body’s treason.” Bawdily, the poet degrades the relationship to an erotic level in which the image of his erect penis is the controlling image of the sonnet: “. . . flesh stays no farther reason, / But, rising at thy name, does point out thee / As his triumphant prize.”
The phrase “To stand in thy affairs” suggests sexual penetration, and the sonnet ends with yet another image of the poet’s erection: “Her ‘love’ for whose dear love I rise and fall.”
English audio from YouTube Channel Socratica
Summary from Cliffsnotes.com