In literature, whether it be a novel, a story, or a poem, there is not necessarily just one correct answer to the question of what the theme is. A literary text can have more than one theme, and many do. What I think might be helpful is for you to...
In literature, whether it be a novel, a story, or a poem, there is not necessarily just one correct answer to the question of what the theme is. A literary text can have more than one theme, and many do. What I think might be helpful is for you to have a better understanding of what a theme is.
A theme is a timeless and/or universal message that the author wants you to come away with after reading the literary work. A successful author will be able to put you in a frame of mind to keep thinking about that message and its importance. Authors seldom state directly what that message is, so it is up to you to figure it out from your reading. We do this by looking at the setting, the characters, and the plot. We do this by noticing symbols and by examining the point of view in the text. We take note of the kinds of words and imagery the writer uses. All of this can add up to a theme.
For instance, when I read the novel The Kite Runner (Hosseini), I see a few themes. I see the theme of redemption. I see what is called a "coming of age" novel, which has a theme of the main character gaining maturity. I see the timeless conflict between fathers and sons. There is a theme of ethnic and religious injustice. Notice that these are all ideas that are important to most people in most times and places. All of them are themes that I see by nature of my analyzing the text itself, finding examples of each in the story.
I do not know what poem you are expected to name a theme for, so read it carefully and ask yourself what message or messages you think the author wants you to understand after your reading. Read the poem more than once, to be sure you understand every line, and if you do not understand something in the poem, get some help, from eNotes or perhaps from a teacher. Try to paraphrase the poem in everyday language that you would use to share the ideas in the poem with a friend if it is written in an old-fashioned way. Once the poem is yours this way, it will be much easier for you to see what themes there might be.