Did Roman Law Actually Prohibit Marriage Between Yahudim and Christianoi?

Late 4th c. · Codex Theodosianus 3.7.2 · Valentinian II, Theodosius I, Arcadius · 388 CE

What the ancient record says

Yes, one of the clearest examples of religious separation becoming civil law. A 388 CE law prohibited marriage between Yahudim and Christianoi.

Not merely "discouraged", it placed such marriages under the legal category associated with prohibited sexual unions; the traditional translation connects violations with the accusation of adultery. Development: sermons against participation, then canons against shared festivals, then canons against unleavened bread, then now the state reaches into marriage; who you could legally marry became part of the religious boundary.

Does not prove no intermarriage ever occurred again, a law proves prohibition, not perfect compliance; its existence suggests intermarriage was a real enough possibility to legislate. Not Constantine's law, the 388 law belongs to Valentinian II, Theodosius I, and Arcadius; do not place every anti-Yahudi Roman law under Constantine.