The Christological controversies
Juvenal's episcopate coincided with the decades in which the Church defined how the divine and human are united in the one person of Christ. At Ephesus in 431 he stood with Cyril of Alexandria against the teaching of Nestorius, which was held to divide Christ's natures. Eighteen years later, at the council of 449, he was reckoned among the leaders favorable to Dioscorus of Alexandria.
At Chalcedon in 451 he changed course decisively, affirming the confession of two natures in one Christ, without separation and without confusion, and concurring in the condemnation of Dioscorus. The anchor record summarizes this trajectory as standing for the Orthodox faith at the councils through the stormy years of controversy.
The elevation of Jerusalem
A persistent aim of Juvenal's tenure was to raise the dignity of the see of the Holy City. His attempt at Ephesus to secure precedence over Caesarea and Antioch went unsupported, but at Chalcedon an arrangement with Maximus of Antioch granted Jerusalem jurisdiction over the Palestinian provinces.
This settlement set Jerusalem on the path to patriarchal rank among the historic sees of Rome, Alexandria, Antioch, and Constantinople, a status the Church would come to recognize for the mother church of Palestine.
Revolt and restoration
Juvenal's acceptance of Chalcedon was bitterly resisted in Palestine. Monks loyal to Dioscorus went into open revolt; according to the sources their leader Theodosius seized Jerusalem with violence and was installed in Juvenal's place, while Bishop Severianus of Scythopolis was killed amid the disorder.
Although he kept the support of figures such as Euthymius the Great, Juvenal was driven out and fled to the capital. He was restored by imperial troops in 453 and governed without further upheaval until his repose.