Daniel Defoe's A Journal of the Plague Year was set in the years 1664 and 1665 during the Great Plague of London, when the city was afflicted with a massive outbreak of bubonic plague, with death tolls estimated at 8,000 per week. The plague was terrifying because the medical science of the time could not explain what caused it or how it spread. One of the major ways people thought about the plague was with respect to religion.
Causes of the Plague: In the Bible, God sent ten plagues against the Egyptians, and other plagues and diseases as punishment to impious individuals or groups of people. Thus many of the characters in Defoe's book wonder if the plague is some form of divine punishment, and various individual preachers and sects spring up around this concept, often arguing that certain behaviors or beliefs needed to be changed to make the plague disappear.
Theodicy: During the plague, which struck good and evil alike, and caused tremendous suffering even in innocent young children, many people struggled to reconcile the existence of the plague with a notion of divine justice.
Religious Services: People did understand that quarantining plague victims and avoiding large assemblies of people would retard the spread of the plague. On the other hand, prayer and worship were increasingly the only solace or hope for the populace.
Role of Clergy: Should the clergy actively minister to people suffering from the plague, including offering last rites, or should they stay away from the sick to avoid spreading the plague? This issue was hotly debated, and many of the richer clergy were criticized for fleeing to the countryside, while others were praised for their ceaseless labor in ministering to the victims.
Religious Quarrels: This was a period of strong religious disagreements, in which normally Dissenters, Roman Catholics, and Anglicans were engaged in vitriolic debates. Defoe praises these various sects for putting aside their differences and working and praying together during the plague.