Whoever forgets the difference that exists between the Supreme Lord and the separate being is subject to the conditions of the material world, which implies that they will have to abandon one material body to accept another, and die only to die again.

Lord Krishna says: “I am the foundation of the spiritual being.”

Forgetting and misunderstanding this truth is called “maya,” illusion. It is by forgetting one's own position and that of the Supreme Lord that the distinct being falls into illusion, or conditioned existence.

This is what happens to those who must reincarnate.

God, through visions He brings into our minds, generally between the ages of 20 and 30, gives us proof that we had a previous existence.

Each of us is, in truth, a spiritual soul or spiritual being, and not the dense physical body in which we reside and with which we mistakenly identify. We can prove this through our consciousness, which is actually the soul's energy, its manifestation. This consciousness, spreading throughout the body, takes control and, through the soul's vital force, gives it life. Consciousness is proof of the soul's presence in the body.

In truth, death is merely the end of the physical body's life, which decomposes, and whose various components return to the different realms of the material world from which they originated. The body is, in reality, an inert mass of material elements.

The soul, which is immortal, continues its existence and reincarnates according to the law of karma and the nature of its actions. It therefore has an experience separate from the dense physical body. In reality, the soul is imprisoned in an ethereal body, itself enclosed within a dense physical body. Thus, during reincarnation, it is the ethereal body that transports the soul to its new body, which a new mother will give it in her womb. The celestial beings, who are God's assistants in this process, undertake this wondrous task.

The Supreme Lord, Krishna, says: At the moment of death, the soul takes on a new body, as naturally as it passed, in the previous body, from childhood to youth, then to old age. This change does not disturb one who is conscious of their spiritual nature.

The process of reincarnation continues until the soul is liberated from material existence. And to be liberated from material existence, one simply needs to surrender to Krishna, obey Him, do His divine will, and serve Him with love and devotion forever.

The Lord also said: It is the thoughts and memories of the being at the moment of leaving its body that determine its future condition.

This is why, with these words, Lord Krishna advises us to control our thoughts, words, and actions, for they produce disastrous effects and therefore disastrous consequences if they are rooted in malevolence.

Also, if we have a specific thought, it will be interpreted by God on the one hand, and by the celestial beings on the other, as a desire, and we will then obtain it in our next life.