Many Christians have today accepted the concept of reincarnation. Certainly the Jew cannot hide from it. He cannot hide from the obligations it places upon him which are above the normal requirements of religious observance. These obligations include the study of Jewish mysticism. The concept of hell, purgatory and other punishments of the soul in the afterlife are one part of the truth.
Reincarnation is the other part.
The share which each person receives in the afterlife depends upon the good deeds done in this world. A Jew that lives piously according to the Torah merits to a share in the afterlife. The quality of this share is according to the quality of his service of G-d. Those that excel to the highest excellence receive a greater portion than those that are good people but did not sacrifice all their pleasures in life to do good deeds. Reincarnation allows for these souls whose portions are not yet complete to improve this portion through returning to the world again in a body as a reincarnated soul.