A watered down gospel is no gospel at all. If the biblical gospel message is altered or refuted, it is just another gospel- and no gospel at all. Perhaps one of the all time greatest delusions in the Christian world, is the innumerable number of people who are under the impression that, in order to be forgiven their sins and inherit eternal life, all they have to do is believe Yeshua (Jesus) died for their sins on the cross.
Constantine became Roman Emperor in 306 AD and ruled for 31 years. But also Constantine had a problem. What was he to do with the followers of Yeshua (Jesus) who were spreading rapidly ?? They did keep their strong faith even if they were tortured and killed. So far all Roman Emperors had persecuted the early followers of Yeshua (Jesus)- but were not capable of stopping them. Constantine realized that he cannot stop them either. He did not join them but he made a new religion around another and different Greco- Roman Jesus beside them. With another spirit and another gospel.