Most of the written material of reincarnation is very esoteric,
often written in Aramaic. Some of the prominent works dealing
with this subject are the "Zohar" (1st
century) and the Arizal's "Shaar HaGilgulim"
(16th century). In the Bible itself, the idea is intimated
in Deut. 25:5-10.
Many sources say that a soul has a maximum of three chances
in this world. One example given is that the great Talmudic
sage Hillel was a reincarnation of the Biblical figure Aaron.
The soul only comes into this world in the first place
in order to make a spiritual repair. If that is not fulfilled
by the end of one's lifetime, then the soul will be sent
down once again. The return trip may only be needed for
a short time or in a limited way. This in part explains
why people are born with handicaps or may live a brief life.
(Example someone who would continually bother a cripple
man, his fixing would be to comeback as a cripple man and
feel the pain)
It is not necessary that there be a conscious awareness
in order for the correction to take place. Conscious awareness
is only one level of understanding. This idea is explored
in an interesting book called "Psychic Phenomena,"
by Dorothy Bemar Bradley, M.D., and Robert A. Bradley M.D.:
"Mentally retarded children have been known to burst
out with unexpected abilities under altered awareness, manifesting
the contents of the undamaged and theoretically undamageable
In other words, there are levels of understanding that
transcend the conscious level, even in children.
Truly, most"corrections" do not have to take place
through the body, but rather take place in the soul world,
in the afterlife.
However, sometimes the correction must occur in the physical
world. For example, it may involve a certain challenge of
choosing the "right thing" over choosing the "comfortable
thing." Or other people may have to be involved. And
the soul cannot interact with the physical world in any
other way expect through a body.
The bottom line in all this is that a person's life situation
provides everything necessary to achieve ideal growth. Our
task is simply to employ our free will -- i.e. to properly
and effectively use the opportunities that come up.