Wall icons and artwork appeared in Jewish temples early in ancient history (note: Duros Europos Temple destroyed in the mid 200’s) even before their use in Christian churches.  Because the Son of God took on human flesh and became incarnate as man in Jesus Christ, the Church decreed (not without much debate!) it was appropriate to portray the glory of God incarnate visually through icons. Icons are NOT idols or graven images (which depicted images of false gods), and their place in Christian worship and piety was clearly articulated, defended and approved at the Seventh Ecumenical Council of the Church in the 8TH Century. Byzantine icon style may seem austere and strange at first. They are not meant to depict the natural beauty of the material world, but rather the spiritual beauty of the Kingdom of Heaven and its inhabitants (Saints). Icons are venerated, but not worshipped, by Orthodox Christians. This is a misunderstanding by some in modern Christendom, especially those who have been influenced by Puritan and Anabaptist traditions, and the Islamic tradition, which rejects any and all images.