Reflections on the notion of tolerance, as it is understood today, did not exist during Antiquity, as the concept did not arise until modern times, in post-Reformation Europe. In the Greco-Roman Mediterranean a plurality of religious practices coexisted in a setting of de facto tolerance, overturned by the rise of Christianity, a monotheistic religion with universal claims. During the era of their persecution, Christian apologists' discourse in favour of religious freedom was rooted in the following arguments: 1) the idea that religion was a personal and private choice, which could not be imposed by force 2) the superiority, in philosophical terms, of persuasion over coercion 3) the praxis of Roman policy, which had always respected and preserved the religious ethos of the peoples under its rule, and 4) the right to practice the religion of one's choice as a privilege inherent to Roman citizenship. The aim of this paper is to study apologetic discourse endorsing toleration based on the inter-connection of the third and fourth of these arguments; i.e. religious freedom as one of the rights that the Roman state guaranteed its citizens, as it acknowledged the legitimacy of religious plurality.