Detail from the 15th century work Last Judgment, by Giovanni da Fiesole, also known as Fra Angelico, depicting dancing angels, saints and the gate of heaven.
Alfredo Dagli Orti/The Art Archive/Corbis
Stones placed on a Jewish grave to show respect for the deceased. Orthodox Rabbi Joseph Telushkin says Jewish tradition holds that there is an afterlife but doesn't encourage speculation on what it might be like.
Detail of the central compartment of The Adoration of the Mystic Lamb, completed in 1432 by Jan van Eyck, where pilgrims gather to pay homage to the lamb of God. Many art historians interpret the painting's fountain as a symbol of eternal life.
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