Edmund Spenser is probably best known for The Faerie Queen, written as an idealized notion of Elizabethan England and intended to provide the reader with the means to become a perfect gentleman. In Sonnet 75, "I Wrote her name Upon the Strand," Spenser confirms the enduring nature of love, and even though his love interest suggests that he is wasting his time in attempting to "immortalize" something that is "a mortal thing," he remains steadfast in his attempts, claiming that "Our love shall live, and later life renew." Just as love endures, so do Spenser's attempts. He is not fazed when the tide washes away his first attempts to write about his love. When the tide washes it away, he does it again, even though he knows that the tide will repeat the process, his efforts being "prey" to the tide.
The word "vain," which appears twice in line 5, has been used to convey more than one meaning. The "vain man" suggests that the man is arrogant because he believes that he is more powerful than the natural elements. He expects to be able to outdo the mighty force of the ocean, which makes him conceited and perhaps even egotistical. The second use of the word refers to his worthless attempts; he is wasting his time and his efforts will be ineffective against the tide. It is interesting that the same word almost contradicts itself in this context and the reader must decide whether the man or nature is more powerful. Is the woman justified in thinking that he tries in "vain assay" or is he right to remain consistent in his efforts, revealing his vanity but in fact being ultimately victorious.