What does Jonah and Hercules have in common? Both underwent the mythological rebirth symbolized by being swallowed by a sea monster only to be regurgitated later (sorry, there just isn't a good word for vomit). The symbolism is pretty straight-forward. The womb and the stomach are pretty much in the same place.

This shows the whale more like a sea serpent (Nordic Jormungand?). Anonymous icon (XX Century) Holy Transfiguration Monastery Brookline, MA, USA

This is pretty standard practice in stories and happens quite often, however, with the except of the modern version of being swallowed by a 30 foot cochroach in the modern movie, Men In Black, most of the stores involve sea monsters like whales. Another notable exception is the wolf in Little Red Riding Hood.

Speaking of which, why is it everytime I read another version of the Red Hood story, the swallowing of everyone by the wolf is changed to being locked in the closet. What's up with that? What kind of symbolism are we talking about (unless we are equating rebirth with "coming out of the closet").

Notice how the basket, looks like a coffin in this 17th century painting by Sébastien Bourdon

Womb of Rushes

Another similar symbol is the basket, box or barrel containing a child that floats down the river. This symbol was in vogue long before Moses tried it out, and has made its way in many stories (see the story of Three Golden Hairs for a good example).

Joseph Campbell compares the symbolism of the basket of rushes to the coffin or sarcophagus (of the Egyptian god of rebirth, Osiris). The womb or tomb can be seen as the same thing (symbolically-speaking, of course) for both prepare the body for its eventual birth or resurrection. [See The Hero with a Thousand Faces, page 92, where Joseph Campbell compares going through the jaws of the sea beast with the journey and return from the rebirth ceremonies in the ancient temples.]

For parallels between Joseph and Moses (and how these stories parallel the Egyptian god, Osiris), check out B'shallach by Harry Freedman.

Second Set of Parents

Normally, the symbol of womb of rushes is hooked up with another rebirth symbol of a second set of parents. The first set of parents, give half of the hero's ability (often the aspect of fate, as in both Moses and in Oedipus), and the second set of parents give the other half. The influence of these parents are shown in the two stages of life, but in reverse. For instance, with Moses, the world of the Pharaoh influences Moses as a young adult, but the second half of life belongs to the influence of his infant parents.

In ancient Celtic and Teutonic culture, the second set of parents were faeries, or guardian spirits (also guardian angels). This symbolism was integrated in the Catholic Church by way of the godfather and godmother during the rebirth ceremony (baptism) of the child. This is why Cinderella's faery godmother watches over and helps her during her rebirth into Cinderella's new life as a princess.

Carl Jung discuss this second set of parents (and the rebirth symbolism) as a psychological aspect of the psyche:

Thanks to this motif of the dual birth, children today, instead of having good and evil fairies who magically "adopt" them at birth with blessings or curses, are given sponsors- a "godfather" and a "godmother."

The idea of a second birth is found at all times and in all places. … It is the central mystical experience; it is the key idea in medieval, occult philosophy, and, last but not least, it is an infantile fantasy occurring in numberless children who believe that thier parents are not their real parents but merely foster-parents to whom they were handed over. [from The Concept of the Collective Unconscious, page 63 in the collection of Jung writings, The Portable Jung, edited by Joseph Campbell]

The Orphan

Related to this is the fact that most heros are also orphans. The death of the parents often bring out the necessary change of heart (rebirth) for the hero to embark on his spiritual journey (just look at most hero-oriented movies, like Star Wars to notice this symbol).

Jung also discusses this as another psychological aspect related to a rebirth:

The wine of youth does not always clear with advancing years; sometimes it grows turbid. Their appearance, it seems to me, is often delayed by the fact that the parents of the person in question are still alive. It is then as if the period of youth were being unduly drawn out. I have seen this especially in the case of men whose fathers were long-lived. The death of the father then has the effect of a precipitate and almost catastrophic ripening. [from The Stages of Life, page 13 in the The Portable Jung]