The Christian theme in John Milton's poem “On the Death of a Fair Infant Dying of a Cough” is that the soul's joy in heaven ultimately takes priority over man's earthly existence.

Milton may lament the death of a baby, a “Fairest flower no sooner blown but blasted,” but as a devout Christian, he tries to see the bigger picture. The poor child may have shuffled off this mortal coil, but that doesn't mean that this is the end. There is nothing inglorious in the child's fate, for his “Virgin Soul” will almost certainly ascend to heaven.

In “On the Death of a Fair Infant Dying of a Cough,” as with many of Milton's poems, we see him using elements drawn from classical mythology to convey what are essentially Christian ideas.

In this fusion of the pagan and the Christian, Milton shows himself to be a Christian humanist, someone steeped in classical learning yet at heart a man devoted to Christ's teachings, albeit in Milton's case of a somewhat unorthodox interpretation.

In both pagan and Christian thinking, there is a strong emphasis on the superiority of the soul over the body. And it is this insight that pervades Milton's poem. The child's body may have perished, but his soul lives on, and for Milton the Christian humanist, this is what matters most.