You may not need a concluding paragraph, especially in a short essay. If you do add a concluding paragraph, it should sum up your thesis without sounding redundant. It may even put the issue into a wider perspective or ask a challenging question.
Here is a sample concluding paragraph from the essay on de Maupassant’s "Love":
The descriptive passages show the narrator’s true heart, the icy heart of an articulate, highly intelligent being who is, in the end, a dispassionate Parisian, "chilled to the very marrow." The paradox, breaking the cold hearts of our civilized, rational, sophisticated natures, is, of course, that the primitivism of the birds is the highest form of sensitivity, delicacy, refinement. And the "fearsome" country of the human heart conceals the "unknown and dangerous secret," the inability of civilized humans to love passionately, or even, perhaps, to love at all.