The soul, however, although it can assume higher or lower bodies, remains the same. In all cases, by virtue of the immutable laws of karma, the consciousness a being develops during this life will determine the body they will assume.
God says to this effect: He who dies in the grip of ignorance is reborn
in the animal world.
There is no clinical, scientific, or scriptural evidence to support the view that once one has reached the human level, it is impossible to fall back into the lower species. This idea contradicts the true principles of reincarnation, which millions of people have understood since ancient times.
The Vedic scriptures also explain that it is very rare to obtain a human form. In other words, most beings in this world have assumed non-human forms. This phenomenon occurs when the soul, renouncing the goal of human life, spiritual realization, loses itself in animal desires.
The soul must then be reborn in the form of an animal, or in an even lower kingdom, a plant.
Let us not, however, make the mistake of thinking that after the dissolution of the physical envelope, it will not be possible for us to meet the Lord, for lack of a body. Since the spiritual entity, also called the spirit soul, is unborn, it would be wrong to believe that it begins to exist when the material body is created. Moreover, the creation and evolution of the material body only respond to the desire of the being, and it is therefore because of each person's desires that the material body develops.
In conclusion, the spirit soul engenders the body, which thus finds its origin in the living force. When the physical envelope is finally destroyed, the spark of life nonetheless continues to exist, just like the air that was also present in the body. Thus, by the will of the Lord, who watches over the welfare of all beings, the distinct soul is immediately granted the special spirit body that will allow it to enjoy the Lord's company according to one or other of the perfections it has attained: one that allows it to possess the same bodily traits as the Lord; one that allows it to live on the same planet as the Lord; one that allows it to enjoy the same opulence as the Lord; and one that allows it to live in the Lord's company.
The Lord's benevolence is such that even if a virtuous being does not reach a stage of pure devotion free from all material defilement, it will be granted to him to attain it in his next life. By being reborn into a wealthy family or among devotees of the Lord, the virtuous spiritualist will not have to engage in the harsh struggle for material existence, and will thus be able to complete his purification. When he finally leaves his body, he will immediately return to the kingdom of God, his original home. When he reaches the spiritual level, he then remains there eternally.


