The myth of exodus is distinguished from the myth of return by repetitive stages of ritual, moving linearly through time, rather than by cyclic recurrence. Exodus mythologizes the means by which man will eventually reach heaven: through successive stages of trial and purgation. The Exodus of the Israelites from the bondage of Egypt into a wilderness is a metaphor for faith in the outcome of trial and purgation; it is a type of the leading of Jesus into the desert. Paradise Lost, while frequently citing biblical accounts connected with the Exodus, presents the original mythic occurrence of exodus as Adam and Eve leave their formerly secure world to embark upon the wilderness of life. The successive exoduses of man are shown in Books XI and XII. The exodus myth exists further in the fabric of the poem in the roles played by Moses, Raphael, and Michael. The aim of successive exoduses is to transform the hardened heart into “th'upright heart and pure,” to achieve the Paradise within. The hortus conclusus out of which Adam and Eve emerge to face the world before them indicates the source of the myth: the delivery of the child from its mother's womb.