Q. Does Jesus have a soul?
A. Your question was raised in the early centuries of the Church. Christians at that time were trying to figure out more accurately the nature of the Incarnation — what it means to say that “the Word became flesh and dwelt among us” (John 1:14).
In time, the Church gave a definitive answer: When God the Son became a Man, He took for himself a complete human nature. The human nature that He took (the technical theological term is “assumed”) included everything that makes us human.
So what does this include? Human beings are composed of both a body and a spirit. The body and spirit are not two natures, but two components so intimately joined that they form together a single human nature.
Are spirit and soul the same thing? In human beings (though not in other living creatures on earth), yes: Their immortal spirit, created by God, functions as their soul, which is defined as the animating principle of a body — that is, the thing that gives life to the body. (When the spirit departs, the body dies.) The term spirit, then, refers to what it is, its essence; the term soul refers to what it does, its function.
As a rough analogy, consider the rock that sits on a stack of papers on my desk. If you ask what it is, I say it’s a rock. If you ask what it does, I say it’s a paperweight.
Because this single human nature is composed of both body and soul (spirit), when God the Son became a Man, He took for himself not only a human body, but also a human soul. This means that the Incarnate God had (and will always have — He will never lose them) two natures: one divine, and one human, with the human nature being composed of both body and soul.
Why was it so important for the Church to clarify this reality? Because, as the Church Fathers often emphasized, the purpose of the Incarnation was to heal and save human nature. If some part of that nature was not included in the Incarnation, neither would it have been saved and healed.
Do we fallen human beings need healing in our souls? Of course! Jesus came to heal the disorder of our souls: our thinking, our will, our emotions. So He took a human soul as well as a body.
This reality is reflected in the traditional formulation that when we receive Our Lord in the Eucharist, we are receiving not only His Body and Blood, but also His “Soul and Divinity.” His Body and Soul are so intimately joined, and His Humanity and Divinity so completely in union, that to receive any one of these is to receive them all — the whole Person, Jesus Christ, the Son of God in the flesh.