The Palestinian-Georgian calendar venerates him on December 16 and October 19 in the Acta Sanctorum.
As an adult he was sold as a slave in Egypt, but converted his pagan master to Christianity and was freed by him.
Withdrawing to Mount Sinai to live as an ascetic, he was later made abbot of the Monastery of St. Theodosius in Palestine.
[4] He became patriarch in his own right after Zacharias died in Persia when Heraclius visited the city to restore the True Cross in March 630.
On Modestus's death he was buried in the Church of the Eleona on the Mount of Olives.