Form of christianity based on greek heritage practiced in the byzantine empire

Orthodox Christianity

Explanation:

The Orthodox Christianity was the form of Christianity that was practiced in the Byzantine Empire after the split of the Church into two divisions. This type of Christianity was practiced on the territory of the Byzantine Empire, thus Asia Minor, parts of the Middle East, and the Balkans, later Russia as well. Unlike the Catholic Church, the Orthodox one was never given too much power, and it has been separated from the government for almost all of the time in all of the places where it has been practiced. It has also been much less restrictive toward its followers as to what should they do, when should they go to church, how to live their lives etc.  

d.summerains, the last one