Final answer:
Pagans used the term 'atheist' as the worst insult against Christians. The refusal of Christians to participate in animal sacrifices in honor of pagan gods was interpreted as atheism by Roman officials. Over time, the Roman Empire officially became Christian, leading to the suppression and persecution of traditional pagan practices.
Step-by-step explanation:
The worst insult that pagans used against Christians was considered to be 'atheist'. Roman officials often characterized Christians this way due to their refusal to perform animal sacrifices common in pagan worship. Over time, as the Roman Empire became more Christian, the tide of persecution turned, and Christians undertook violent measures against pagans, even leading to the murder of pagan philosopher Hypatia in Alexandria. Eventually, the empire, once heavily influenced by polytheism, officially became Christian under Emperor Theodosius I in 380 CE, leading to the decline of traditional pagan worship.
When understanding this period of religious transition, it is crucial to comprehend the nuanced strategies of Christian leaders, such as Pope Gregory's advice to repurpose pagan temples for Christian worship, and other forms of syncretism which helped Christianity to become deeply rooted in the empire. While Christianity prevailed over paganism in terms of state support, many pagan practices and beliefs related to magic and spirits persisted and even influenced Christian customs, reflecting both religions' belief in the supernatural.