Limbo: Circle 1, Inferno 4   The concept of Limbo--a region on the edge of hell (limbus means "hem" or "border") for those who are not saved even though they did not sin--exists in Christian theology by Dante's time, but the poet's version of this region is more generous than most. Dante's Limbo--technically the first circle of hell--includes virtuous non-Christian adults in addition to unbaptized infants. We thus find here many of the great heroes, thinkers, and creative minds of ancient Greece and Rome as well as such medieval non-Christians as Saladin, Sultan of Egypt in the late twelfth century, and the great Islamic philosophers Avicenna (Ibn Sina) and Averroës (Ibn Rushd). For Dante, Limbo was also the home of major figures from the Hebrew Bible, who--according to Christian theology--were "liberated" by Jesus following his crucifixion (see Harrowing of Hell).