"We decree with full precision and care that, like the figure of the honored and life-giving cross, the revered and holy images, whether painted or made of mosaic or of other suitable material, are to be exposed in the holy churches of God, on sacred instruments and vestments, on walls and panels, in houses and by public ways; these are the images of our Lord, God and Savior, Jesus Christ, and of Our Lady without blemish, the holy God-bearer, and of the revered angels, and of any of the saintly holy men." -
Second Council of Nicaea (Seventh Ecumenical Council) - 787 A.D.