The Foundation Stone Haggadah: Themes of the Haggadah 2: Kadeish
The body can be compared to a governor that has been placed on the soul. (I once rented a U-Haul truck and a governor had been installed on the engine so that it wouldn’t go faster than 55mph. If you wanted to drive the truck cross-country, you’d have to break it off.) No matter how much the soul grows, it remains stifled. In fact, in perfecting the body, the soul becomes more visible, because it can never fully experience the joy of having accomplished any of its spiritual goals. When the body and the soul are separated, the body, a symbol of evil or physical drives, has to go through a period of decomposition so that its essence is broken down. The soul, unfettered but not free, goes into a place called Olam haNishamot, or the Soul World. In the Soul World, the soul, no longer inhibited by the body, can fully experience its growth.
Even if a person has been studying Torah for 20 years, or keeping Shabbat all his life, he does not fully experience the spiritual growth that should have resulted from all that effort. The effort invested would suggest that the soul is growing. But we don’t feel it, because the body doesn’t allow it. As the soul expands, the body limits its growth. When the soul leaves the body, and goes through the necessary stages, the soul can fully experience its own growth. In doing so, it becomes a much more powerful spiritual existence.
At the time of the Resurrection of the Dead, you will have a newly constructed body, without any of the evil that became a part of it. The body will be neutral, so that when the soul re-enters it, the body will be completely overpowered by the soul. Having perfected the body, the soul has emulated God, and therefore earns permanent, eternal existance, which is Olam Habah.
It is not that the body is recreated, and then you enter Olam Habah. You go through several stages. The more powerful your soul is, the more powerful the degree of perfection of your body is. This results in a higher degree of emulation of God. This in turn, results in a more powerful and higher level of existance experienced in the Eternal World. That is what we are working towards.