Upvote:4
Constantine had a dream about God telling him to put crosses on his soldier's shield and he did and his soldiers won the battle even though they were outnumbered 2:1. He converted and therefore thought he was an instrument of God to stop persecution of Christianity in Rome and legalize it.
Upvote:4
This question cannot be answered. No sufficiant primary or secondary sources exist. We know that Constantine made this opinion known in public (great tool to rally the troops) but whether or not he believed it personally cannot be known from extan sources.