Among Donne’s numerous love poems, "A Valediction: Forbidding Mourning" is one of the most exquisite poems, particularly as it is the expression of a love which is human as well as Divine. He wrote this poem in 1611 or 1612, for his wife, before departing on a trip to continental Europe. According to Elizabeth Reninger, the poem is rich with alchemical and astronomical references, and employs the literary device known as a “conceit” -- i.e. an extended metaphor, in which two objects or events not commonly thought to be related, are shown indeed to resemble one another.
According to the religious view prevalent in Donne’s time, virtuous men live even after their death. In the same way, although his separation from his wife will be a kind of temporary death, he will remain ‘alive’ in the thoughts of his wife during his absence. So he says, “Let us melt” without making noise. Donne uses the exaggeration which he used in his poem ‘Canonization’ and asks her to make sure that there are “No tear-floods, nor sigh-tempests.” According to him it would be a kind of sacrilege to engage in such dramatic expressions of emotion. It would diminish their love’s deeper significance. So here Donne is introducing the distinction between sacred and mundane expressions of love. Then he again compares the high love with the common earthly love by comparing the “trepidation of the spheres” with “moving of the earth.”
Donne believes that absence from the beloved is a high kind of separation which only spiritual lovers can understand:
Dull sublunary lovers' love
(Whose soul is sense) cannot admit
Absence . . .
Then Donne introduces the metaphor which he has used in a number of poems, that is, the two lovers have one soul (“Our two souls therefore, which are one’). Here he uses an extended metaphor. Gold can be beaten into a very thin and long wire. As their souls are one, when he goes away from her, he is still with her. He will be like the expansion of gold. Thus their spirits are infinite and indestructible. He writes:
Our two souls therefore, which are one,
Though I must go, endure not yet
A breach, but an expansion,
Like gold to airy thinness beat.
Thus Donne celebrates the spiritual quality of love in a relationship which is purely earthly.
By comparing his wife and himself to the celestial bodies, such as the sun and others stars, he transcends the worldly and brings his love for his wife to the spiritual level.