|Andrea del Verrocchio and Leonardo da Vinci.|
Symbols of God the Father. Until the twelfth century the only symbol used to indicate God the Father was a hand issuing from the clouds. It was generally represented in the act of benediction, sometimes encircled by a cruciform nimbus, sometimes entirely open with rays proceeding from each finger. It was then supposed to be in the act of bestowing. This symbol was followed by a face in the clouds, then a bust, and by the end of the fourteenth century the entire figure was represented. Then a sentiment grew into being that, as no mortal had seen nor could see him, any attempt to represent him in human form was profane; and since the sixteenth century the Supreme Being has been symbolized by a triangle, the geometrical emblem of the Divine Trinity, or by a radiating circle, itself the symbol of eternity.
Symbols of God the Son. The symbols of Christ are the glory, aureole, or nimbus, the cross, lamb, and lion. However, from the beginning of Christian art, Christ has been represented by portraits rather than symbols, and these portraits are always unmistakable.
Symbols of the Holy Ghost. From the sixth century the dove has been the universal symbol of the Holy Ghost. The representation of the Savior surrounded by seven doves is highly symbolical. They are emblems of the seven gifts of the spirit with which He was endowed: wisdom, understanding, counsel, strength, knowledge, piety, and fear (Is. xi). During the Middle-Ages seven was considered a mystic number. There were seven gifts of the Holy Ghost; seven planets; seven days of the week; seven branches on the candlestick of Moses; seven sacraments; seven stars; seven liberal arts; seven symbolic trumpets; seven churches of Asia; seven mysterious seals; seven heads of the Dragon; seven penitential psalms; seven joys and seven sorrows of the Virgin; seven deadly sins; seven canonical hours.
Symbols of the Trinity. In early art the Divine Three in One was symbolized by the combination of three triangles, three circles, three fishes, and in later art by three human figures, each with its peculiar attribute. In the thirteenth and fourteenth centuries the dove was often represented hovering between the first and second persons of the Trinity with the tips of the wings touching the lips of each.