What policy did Constantine issue in 313 that reversed the persecution of Christians?

The policy issued by Constantine in 313 that reversed the persecution of Christians is known as the Edict of Milan. This significant decree granted religious tolerance throughout the Roman Empire, allowing Christians to practice their faith openly without fear of persecution. It signaled a major turning point in the history of Christianity, moving it from a marginalized sect to a legally recognized religion within the empire. The Edict of Milan is crucial as it marked the end of over two centuries of intermittent persecution, beginning with the violent reign of Emperor Nero and continuing through subsequent emperors.

In addition to its importance in promoting religious freedom, the Edict aimed at unifying the empire and strengthening its moral fabric by recognizing the legitimacy of Christianity. This laid the groundwork for Christianity to eventually become the official state religion under later emperors.

Other options, such as the Nicene Creed and the Council of Nicaea, relate to theological discussions and the formalization of Christian doctrine, which occurred later in the 4th century. Meanwhile, the Twelve Tables were an early codification of Roman law, entirely unrelated to Christian practice or persecution. Hence, the Edict of Milan stands out as a pivotal moment for Christians in the Roman Empire.