When Christianity suddenly went from being persecuted to being sought after and included a lot changed for the Church, not all of it for the better. This is that story.
Some other changes that Constantine brought in that I did not have time to include:
-He formally set Sunday as the day or rest and worship.
-That Constantine considered himself over the Christian Church like he was the head of the pagan churches, and thought of himself as the 13th apostle.
-The change in perception of martyrdom, from the height of religion to something to be avoided.
-How he brought back into the fold people who had renounced their faith under torture, because there were not enough people to teach the faith to the masses otherwise.
-The use of images of the cross as religious icons dates to the time of Constantine as well.
For more information, I highly recommend Pagan Christianity?: Exploring the Roots of Our Church Practices by Frank Viola and George Barna. I am particularly indebted to the later book for starting my exploration on this subject. For a good overview of the time period, I recommend The Catholic Church by Hans Kung. Other references uses include: The Story of Christian Theology by Roger Olson, A People’s History of Christianity by Diana Butler Bass, and The Early Church by E. Glenn Hinson.
Also, here are several websites for more information on how average churches today spend their money.