[5] A polymath whose fields of interest and contribution included law, theology, philosophy, and music, he was given the by-name of Chrysorroas (Χρυσορρόας, literally "streaming with gold", i.e. "the golden speaker").

[8] He was also a prominent exponent of perichoresis, and employed the concept as a technical term to describe both the interpenetration of the divine and human natures of Christ and the relationship between the hypostases of the Trinity.

[11] Written from a hagiographical point of view and prone to exaggeration and some legendary details, it is not the best historical source for his life, but is widely reproduced and considered to contain elements of some value.

[18][19] Mansur seems to have played a role in the capitulation of Damascus to the troops of Khalid ibn al-Walid in 635 after securing favorable conditions of surrender.

"[23] When Syria was conquered by the Muslim Arabs in the 630s, the court at Damascus retained its large complement of Christian civil servants, John's grandfather among them.

[31][32] One account identifies his tutor as a monk by the name of Cosmas, who had been kidnapped by Arabs from his home in Sicily, and for whom John's father paid a great price.

One source suggests John left Damascus to become a monk around 706, when al-Walid I increased the Islamicisation of the Caliphate's administration.

[34] This is uncertain, as Muslim sources only mention that his father Sarjun (Sergius) left the administration around this time, and fail to name John at all.

[24] During the next two decades, culminating in the Siege of Constantinople (717-718), the Umayyad Caliphate progressively occupied the borderlands of the Byzantine Empire.

[35] In the early 8th century, iconoclasm, a movement opposed to the veneration of icons, gained acceptance in the Byzantine court.

[36] All agree that John of Damascus undertook a spirited defence of holy images in three separate publications.

He not only attacked the Byzantine emperor, but adopted a simplified style that allowed the controversy to be followed by the common people, stirring rebellion among the iconoclasts.

Decades after his death, John's writings would play an important role during the Second Council of Nicaea (787), which convened to settle the icon dispute.

[37] Leo III reportedly sent forged documents to the caliph which implicated John in a plot to attack Damascus.

"[56] Some of the Muslims, John says, claimed that the Old Testament that Christians believe foretells Jesus' coming is misinterpreted, while other Muslims claimed that the Jews edited the Old Testament so as to deceive Christians (possibly into believing Jesus is God, but John does not say).

John claims that he told the Muslims that the black stone in Mecca was the head of a statue of Aphrodite.

[57] Later in the 10th century, Antony, superior of the monastery of St. Simon (near Antioch) translated a corpus of John Damascene.

In his introduction to John's work, Sylvestre patriarch of Antioch (1724–1766) said that Antony was monk at Saint Saba.