There is a great deal of "fuzziness of thinking" regarding death that many Christians hold besides reincarnation, Barstad added, such as believing that after death one dies and goes to heaven and stays there forever, rather than joining with their resurrected body at the end of time.
"The vague notion that something called a soul or a spirit or a shade lingers after death in some kind of place or condition where it can be more or less happy is not Christian," Barstad said. "A human soul without a body is a tragedy. Think about what a body is to the soul. It is the instrument, the nexus, the node, the vessel through which, by which, in which a soul establishes and sustains contact with reality," he added.
A body, he said, has concretely experienced everything that a soul has gone through in its lifetime. It is the actual mode through which the soul has related to others. It makes that person who they are - the father of a particular son, or the daughter of a particular mother, the wife of a particular husband, or the friend of a particular person.
"A soul stripped completely of its body is literally nobody. Who cares whether such a nobody lives forever! A Christian is someone who wants to be this somebody...now and after death and unto the ages of ages. But for that to be possible, I'll need my body resurrected along with the bodies of everyone and everything I have a relationship with," he said.
"I have to die completely and be dissolved back into the dust from which I came; and then I have to be put back together again in a new kind of life," he said. "The trouble is I would cease to exist at the midpoint of this process. Someone else has to hold me in being as I pass over from death to new life. Only because Christ loves me am I held in being, not just my soul, the nobody, but the somebody I am because I have this body."
Why Christians should reject reincarnation
The two main reasons that a Christian should reject reincarnation is that it is opposed to the way of salvation offered by Christ, and because it goes against the nature of the human person, Root said.
"It contradicts the picture of salvation that we have in the New Testament, where our participation in Christ's resurrection is what salvation is all about," Root said, "and it gives us quite a different picture of what it is to be a human being - a disembodied self that isn't related to any particular time."
"Christianity takes very seriously that we are embodied beings, and any notion of reincarnation means that the real self only has a kind of accidental connection to any specific body, because you'll go on to another body and another body and another body, and bodiliness ends up being kind of at best side point about who you are," he said.
The belief in the resurrection is bound up with a Christian view of the human person, Root said, which is that a person will only ever have one particular body, and what happens in that particular body matters.
"There's very little formal Catholic dogma about the resurrection details, but one that there is is that we will rise in the same body we now have. There's no official definition of what 'same' is here, and there's a big transformation, but nevertheless it is official Catholic dogma that we will rise in the body we now have," he said.
The transformation of the body can be seen in the resurrected Christ who, once resurrected, was able to walk through walls, appear or disappear suddenly, and seemingly control who was able to recognize him, though he maintained his body, Root noted.
(Story continues below)
Subscribe to our daily newsletter
The Christian view of the human person also means that what happens with each person's body matters. In the document "Jesus Christ: The Bearer of the Water of Life" by the Pontifical Councils for Culture and for Interreligious Dialogue, the Vatican said that belief in reincarnation is incompatible with Christianity because it denies the freedom and responsibility of persons who act through their bodies.
Reincarnation is "irreconcilable with the Christian belief that a human person is a distinct being, who lives one life, for which he or she is fully responsible: this understanding of the person puts into question both responsibility and freedom," the document states. A Christian occupies a body, which is able to be judged for its sins, but is also able to participate in Christ's redemptive work through its suffering, the Vatican noted.
"In bringing about the redemption through suffering, Christ has also raised human suffering to the level of the redemption. Thus each man in his suffering can also become a sharer in the redemptive suffering of Christ," the document states.
Barstad noted that the New Age belief in reincarnation as something positive even contradicts most traditional religions that believe in reincarnation, such as Buddhism and Hinduism, which ultimately view reincarnation as something to be escaped.
"I am not aware of any robust doctrine of reincarnation, whether that of Western Platonists or Eastern Buddhists, that regards reincarnation of a soul as a good thing; maybe certain Hindus or a Stoic could see it as a benign cosmic necessity, like the physical laws governing the conservation of energy," he said.
"But certainly the deepest aspiration of Platonists and Buddhists is to dissolve the nexus of temporal, bodily relationships once and for all; that is, to dissolve the relationship to body so completely that no further embodiment is possible for that soul. The goal is for the soul to become completely and permanently nobody."
The hope of the resurrection