Prior to Constantine, the Roman Empire had a well established social and religious pecking order. The traditional Greco-Roman citizens and Greco-Roman religions were at the top and the Christians, who were traditionally viewed as annoying and deviant, were at the bottom. This socio-religious positioning led to the disdain and persecution of Christians throughout the centuries. However, as Constantine gained sole control of the Roman Empire, the socio-religious landscape began to drastically change. Constantine believed that the best move for restoring the Roman Empire to its ancient glory was by acknowledging the power of the Christian God and giving Christianity superior status. Thus, Christians were no longer persecuted, and they became legitimate and advantaged citizens. This new positioning of Christianity did not abolish the traditional Greco-Roman religions, but it lessened their influence and relevance within the empire which contributed to the expansion of the gospel and of the Christian church.
This new order and relationship between the Roman Empire and the church had both positive and negative aspects. As for the positives, the Christian church had a chance to breathe and regroup from the centuries of persecution. This certainly would have given the Christians a chance to experience the joy of the Lord apart from the fear of persecution and death. They would have been able to reimagine hope and peace in Christ. Another positive is that the church had a chance to focus on other doctrinal issues that needed to be addressed. With more freedom to move within the empire, Christian leaders were able to meet at church councils in order to debate theological ideas and establish orthodoxy. Furthermore, Christians were able to establish themselves in physical churches which would enable them to better organize gospel ministry and establish kingdom of God beacons within the Empire.
As for the negatives, the new “privileges, prestige and power now granted to church leaders soon led to acts of arrogance and even to corruption” which initiated a slow compromise of and shift away from earlier Christian values and ethics. Moreover, Christians were seduced by the power of the Empire rather than focusing on a kingdom of God ethos. There was a distorted understanding of the relationship between worldly power and heavenly power. They falsely equated a worldly conquering empire with the rule and reign of the crucified, suffering servant. The new Christian emphasis on power, riches, prestige and comfort was antithetical to the life and ministry of Christ the King.
While I believe that Constantine played a major role in God’s sovereign plan to benefit the Christian Church during this era, I do think that many of the changes were detrimental to the development of the church throughout the following centuries and even into the present day. I believe that the detrimental aspects are due to the sin corruption of human hearts, but despite the human proclivity to mess things up, God still moved and worked all things together for the benefit of his church (Rom 8:28).
 Justo L.González, The Story of Christianity, Rev. and Updated, 2nd ed. (New York: HarperOne, 2010), EPUB edition, pt.2, ch. 13, “From Rome To Constantinople.”  González, The Story, EPUB edition, pt.2, ch. 13, “The Impact of the New Order.”  González, The Story, EPUB edition, pt.2, ch. 13, “The Impact of the New Order.”