One theme of this poem is that life is unpredictable and that accidents are simply a part of life. The speaker says that, when the major event of the poem occurs (the boy's hand being cut off), the "day was all but done." The men might have told the boy to "Call it a day," giving him the last half hour of the day off, and the boy would have been made so happy by the gift of these few stolen moments free from work. Any small difference or change in the afternoon might have put the boy in a different place so that he was not there to hold the saw and be mortally wounded by it. No one could have predicted that such a horrific accident would occur, and the boy certainly had done nothing to deserve the accident that befell him. Put simply, accidents happen.

Next, though the accident is quick and tragic and results in the boy's death, people move on relatively promptly afterward because life must go on. The speaker tells us that, in the end, the people who surround the boy when he dies "turned to their affairs" since "they / Were not the one dead." Though the person watching over the boy "took fright" when the boy takes his last breath—and they listen to his heart in disbelief that his young life should be snuffed out so quickly—they have responsibilities and tasks yet to be done. They did not die, and so they must continue to attend to the duties of life, whatever those duties may be for them personally. We see how life can and must move on after tragedy: witnessing tragedy does not suspend the responsibilities one has. The living must carry on after the dead are gone, and they do.

Finally, the poem conveys the idea that life is fragile and can be extinguished almost as quickly as a candle. The title refers to a line from Shakespeare's play Macbeth when the titular character compares life to a candle. In the poem, we see how quickly the young boy's life is ended, almost as quickly as blowing out a candle's flame. It's as though such a thing is insignificant because it can be cut off (or put out) so fast.