When the individuated, embodied part of Spirit, the Soul, has completed what it set out to accomplish in a lifetime, it has three basic options: take on a new life goal (Reincarnation-in-Same-Body), die, or walk out. If the Soul chooses to walk out, an agreement is made with another Soul to walk-in and continue the embodiment. This is not possession. It is not a requirement that a person be a walk-in to ascend. It is simply an individual agreement and another way of entering onto the planet.
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