Although it occurs in only one patristic text and in no classical Roman sources or inscriptions, the phrase has spawned abundant scholarly conjecture on its possible significance. Some scholars have gone so far as to imagine that all religions under the Empire had a legal status as either licita or illicita, despite the absence of any ancient texts referring to these categories. The most extreme view has held that Tertullian's phrase means all foreign religions required a license from the Roman government. But it was Roman custom to permit or even encourage the subject peoples of the provinces and foreign communities in Rome to maintain their ancestral religion, unless specific practices were regarded as disruptive or subversive: "A religio was licita for a particular group on the basis of tribe or nationality and traditional practices, coupled with the proviso that its rites were not offensive to the Roman people or its gods."
Religio licita has sometimes been taken as a formal recognition or charter originating with Julius Caesar and embodied by various pieces of Roman legislation pertaining to the Jews, conceived of as a coherent policy. In fact, the various privileges and exemptions granted to the Jews were responses to specific complaints or requests, made in the context of the traditional patronage network, and had nothing to do with a supposed religio licita status. To the extent that the Romans respected Judaism, it was because of the religion's great antiquity, ancestral tradition being regarded as a source of social and political stability.
It has been observed that "Roman magistrates treated the Jews the way they did not because they were consciously tolerant, but simply because they had no reason to hinder the free exercise of Jewish religious practices."