He legalized and standardized the Christian religion.
Explanation:
Emperor Constantine was one of the Roman emperor who took up leadership after the death of the previous emperor. During his reign, there were other Roman general who laid claim to the Emperor title leading to War.
In the course of war, Constantine was drawn to Christianity when he saw an image of Mary. <em>This made him to pledge that, should he win the war, he is going to make the Christianity the official State Religion. After defeating his enemies, he then, legalized and standardized the Christian religion.</em>
