There is a History of the Byzantines podcast and it talks about the political maneuvering in the empire and church. They had political parties and each party had separate religious beliefs and that was important for how church doctrine evolved.

It's so incredibly political it's unbelievable. It's like "I want to be emperor so I will agree to whatever those guys say so I can gain their political support". And now hundreds of millions of people think that's the word of God when really it's the back alley dealings of Justinian.