Why were Christian Apologists writing in the second and early third centuries?

Christian Apologists in the second and early third centuries wrote to defend the faith while engaging in battle on two primary fronts: external criticism and internal dissent.12

External Defense

Apologists sought to protect the church from the hostility of pagan society and the intellectual attacks of Greco-Roman critics. Because of the church’s aloofness from public life, Christians were frequently targets of popular, spurious rumors, including accusations of atheism, cannibalism, and promiscuity. Apologists worked to refute these charges, demonstrate the moral superiority of Christianity, and prove the antiquity of their religion by presenting it as the fulfillment of Hebrew Bible prophecy. To appeal to the sophisticated sensibilities of their contemporaries, they adopted the philosophical and literary vocabulary of the broader culture, often utilizing the concept of the Logos to explain Christian doctrine.32145

Internal Consolidation

Simultaneously, Apologists defended orthodoxy against distorting tendencies within the church, such as gnosticism and the teachings of Montanus. By addressing these challenges, they helped define the church's stance in relation to Judaism and Hellenistic culture, effectively becoming the first Christian theologians.123