While listening to Gibbon's 'The Decline and Fall of the Roman Empire' I came across the following in Chapter 53:
The spacious provinces of Thrace, Macedonia, and Greece, were obedient to their sceptre; the possession of Cyprus, Rhodes, and Crete, was accompanied by the fifty islands of the Aegean or Holy Sea; and the remnant of their empire transcends the measure of the largest of the European kingdoms.
I am unfamiliar with the reference to the Aegean Sea as the Holy Sea, and I tried investigating. I thought there could be a reference to the Greek or Latin etymology of the word, but an investigation of the word root notes that we don't know the derivation. Furthermore, Wikipedia notes that the sea used to be called the Archipelago by most of the people around it.
Hence, where does Gibbon's reference to the "Holy Sea" come from?