7 Ecumenical councils

325ad , condemns the Arians and declares the Trinity as orthodox

381ad , About the Divinity on the Holy Spirit, influenced by the Cappadocian Fathers

431ad , If Mary is the Theotokos, and if Christ is 2 subjects, against Nestorius

451ad , If there is one or two natures after the union

553ad, clarify the christology of two natures, 1 subject 2 energies, condemned the letter to Ibas, and some of Theodorets writings.

680-681ad, Condemned Monothelitism, which taught that Christ had only one will, and reaffirmed the doctrine of Christ's two wills (divine and human).

787ad, against iconoclasm, Christ can be depicted, Christ's image can be venerated because the veneration is one with his image.