One of Donne's most eloquent love poems, "Valediction: Forbidding Mourning," using language pulled from religion, Petrarch, astronomy, alchemy, and geometry.
(1) Religion: "Virtuous men whisper to their souls to go"; "twere profanation of our joys to tell the laity our love"
(2) Petrarch: "tear-floods"; "sigh-tempests"
(3) Astronomy: "trepidation of the spheres"; "dull sublunary lovers' love"
(4) alchemy: "like gold to airy thinness beat"
(5) geometry: "stiff twin compasses"; "thy firmness makes my circle just"
The language serves to evoke the idea that the love between the two lovers is spiritual, strong, private, perfect, and precious. The language is perfectly matched to the figures of speech; in fact, it comprises the metaphors that Donne uses throughout the poem.
John Donn's "Valediction: Forbidding Mourning" is a metaphysical poem in which the speaker addresses a wife/lover who must remain home while he leaves on a trip.
His main poetic device is the conceit: an elaborate, extended metaphor that connects the theme of physical union with the metaphysical (or spiritual) union.
His conceit is the compass, in which she (the soul) is the point (the fixed leg) who remains static (home), and he is the pencil (the moving leg) who travels. The analogy, of course, is that if she remains home while he travels, together they will form a perfect circle (wedding ring), the symbol of of love and unity. So says Enotes:
“A Valediction: Forbidding Mourning” is a good example of a poem that embodies the theme of this sort of love. By using a conceit that compares his love to a compass, the speaker reminds his absent beloved that the further they grow apart physically, the deeper and more expansive their love becomes spiritually.