Gradually, Peter came to favor another professor from the Kiev's Academy, Theofan Prokopovich, whose 1721 "Spiritual Regulation" supported the concept of a Russian national church under the authority of the Tsar as the "supreme bishop", and argued that an ecclesiastical council would be more appropriate to govern the church than a single patriarch. It seemed dubious to Prokopovich to have a dual power in the Russian Empire and was supportive of the idea of a single and an ultimate autocrat. Among the Russian clergy, however, Prokopovich was perceived as a Lutheranist and a Calvinist as person who studied protestantism and who did not mature in the culture of the Eastern Orthodoxy. Against him energetically protested the rector of the Moscow Academy Theophilakt Lopatinsky when Prokopovich was appointed the Metropolitan of Pskov.