Governance During the Persian Crisis
The defining work of Modestos's episcopate was the rebuilding of Jerusalem after the catastrophe of 614. The Persian conquest had left the holy sites of the city ruined and its leading clergy and people deported. As locum tenens during the long captivity of Patriarch Zacharias, Modestos bore responsibility for the practical restoration of Christian life in the Holy Land.
His life records that the restoration was carried out with the material assistance of Saint John the Merciful, Patriarch of Alexandria, who was renowned for his generosity. Among the shrines repaired was the Church of the Holy Sepulchre, the Tomb of the Lord itself. Modestos is also remembered for gathering and burying the monks who had been killed at the Lavra of Saint Sabbas during the invasion.