Iconography is the branch of art history which studies the identification, description, and the interpretation of the content of images. Ethymologically, the term iconography comes from the Greek εἰκών "image" and γράφειν "to write."
Fernando Gallego, Salvator Mundi, oil, 1485. Museo del Prado, Madrid
Iconographical research is often based on literary sources. Religious images are used to some extent by all major religions, including both Indian and Abrahamic faiths, and often entail highly complex iconography, which reflects centuries of accumulated tradition.
INDIAN SOURCE - Ramayana. Anonymous, Rama, Sita, Lakshmana, and Hanuman, poster
HEBREW TRADITION - Tanakh. Tetragram, Liège, 18th Century
GRAECO-ROMAN MYTH - Iliad. Michelangelo, Rape of Ganymede, 1532
CHRISTIAN SOURCE - Gospel of Luke. Louis Alincbrot, Christ among the Doctors, c. 1460
ISLAMIC TRADITION. Buraq painted on the rear of a Pakistani truck, 2008
Additional examples to keep in mind:
Hans Holbein the Younger, Allegory of the Old and New Testaments, c. 1524, oil on wood, 49 X 61 cm. National Gallery of Scotland, Edinburgh
The Glue Society, The Crossing of the Red Sea, digital image, Australia, 2009
Gallego, The Circumcision, panel from the Retablo of Ciudad Rodrigo, c. 1480-88. Oil and tempera on panel. University of Arizona Museum of Art, Tucson