First, he responds to the argument that the abolition of Christianity would expand the liberty of conscience by arguing that if great wits could not denounce the Church, they might instead turn to the denunciation of the government, causing political unrest.
Answering the argument that the abolition of the gospel would benefit the vulgar, and that religion was put in force to keep the "lower part of the world in awe by fear of invisible powers," Swift points out that the vast majority of people were already unbelievers who only employed religion to quiet "peevish" children and provide topics for amusing discussion.
Swift addresses the argument that abolishing Christianity will contribute to the uniting of a people divided by various sects of by arguing that humanity has an inborn "spirit of opposition" such that if Christianity were not extant to provide a context for such natural oppositions among men, this natural tendency would instead be spent in contravention of the laws and disturbance of the public peace.
First, Swift points out that reformers do not appreciate the advantage to them of having such an easy target upon which to practise their criticism and wit with such little risk to their persons in response as the Church and clergy; and rhetorically asks what institution could adequately replace religion in this role.
Next, Swift warns that the abolition of Christianity (specifically the Anglican church) could lead to a rise in Presbyterianism, or worse in his mind, Catholicism.