As well as “the Baptist”, John is also known as “glorious
prophet and forerunner of Christ”. Therefore, the presence of the wings is to
symbolize John’s status as a divine messenger (in Greek “Evangelos”, from where
the word “Angel” is derived). It’s worth noting that the wings of the
archangels (Gabriel, Michael etc.) in icons are largely symbolic too, as they
are not specifically described as having wings in the Scriptures.
But if that were all, then why aren’t the prophets of the Old
Testament, or the Apostles, shown with the angelic wings of divine messenger?
The answer, in the words of Jesus Christ Himself, is because “among those born
of women there is no one greater than John;” moreover, he is “the culmination
and the crown of the prophets”, as the hymn from the feast of John’s nativity
proclaims. Therefore, St John is an especial example among the Saints of an
earthly “angel” and a heavenly man. As such, he is also described as the “Angel
of the Desert” in the inscriptions of icons.
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She that once was barren now brings forth Christ’s Forerunner,
John, the culmination and the crown of all the Prophets. For when he, in River
Jordan, laid his hand on Him Whom the Prophets preached aforetime, he was
revealed as God the Word’s fore-chosen Prophet, His mighty preacher, and His
Forerunner in grace.
Source: https://iconreader.wordpress.com/2013/08/29/why-does-john-the-baptist-have-wings-in-orthodox-icons/
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