Ensoulment is the joining of an immortal soul to the human body. In the distant past, many Catholics believed that ensoulment occurred a certain number of weeks after conception (and they had a poor understanding of what conception means). Until recently, there was no definitive teaching on when ensoulment occurs. As a result, some Catholics are laboring under the misapprehension that there is currently no magisterial teaching on the subject. Not so.
Life Begins at Conception
The origin of each human life, in body and soul, at conception, is important to the moral definition of abortion.
A. The Incarnation of Our Lord Jesus Christ
1. At the Incarnation, the Son of God assumed a human nature composed of a rational soul and a body.
Council of Ephesus: “For if it is necessary to believe that being God by nature he became flesh, that is man ensouled with a rational soul….” [Council of Ephesus, Third Letter of Cyril to Nestorius, approved by the Council.]
Council of Ephesus: “We confess, then, our lord Jesus Christ, the only begotten Son of God, perfect God, and perfect man of a rational soul and a body, begotten before all ages from the Father in his godhead, the same in the last days, for us and for our salvation, born of Mary the virgin, according to his humanity, one and the same consubstantial with the Father in godhead and consubstantial with us in humanity, for a union of two natures took place.” [Council of Ephesus, Formula of union between Cyril and John of Antioch, approved by the Council.]
2. In His human nature, Jesus is consubstantial with us, and is like us in all respects except for sin. His human nature is like our human nature, and our human nature is like His human nature (except that he is sinless).
Council of Chalcedon: “So, following the saintly fathers, we all with one voice teach the confession of one and the same Son, our Lord Jesus Christ: the same perfect in divinity and perfect in humanity, the same truly God and truly man, of a rational soul and a body; consubstantial with the Father as regards his divinity, and the same consubstantial with us as regards his humanity; like us in all respects except for sin….” [Council of Chalcedon, Definition of the Faith; cf. Hebrews 4:15.]
3. The Incarnation occurred only once, when the Divine Nature of the Eternal Son of God was united to his human nature, body and soul, which was the same moment when his human nature, body and soul, was created.
Saint Thomas Aquinas, citing Saint Gregory the Great: “On the contrary, Gregory says (Moral. xviii): ‘As soon as the angel announced it, as soon as the Spirit came down, the Word was in the womb, within the womb the Word was made flesh.’ ” [St. Thomas Aquinas, Summa Theologica, III, Q. 33, A. 1]
Saint Thomas Aquinas, citing Saint John of Damascus: “On the contrary, Damascene says (De Fide Orth. iii): ‘At the very instant that there was flesh, it was the flesh of the Word of God, it was flesh animated with a rational and intellectual soul.’ ” [St. Thomas Aquinas, Summa Theologica, III, Q. 33, A. 2]
Saint Thomas Aquinas: “On the contrary, Augustine says (De Fide ad Petrum xviii): ‘Hold steadfastly, and doubt not for a moment that Christ’s flesh was not conceived in the Virgin’s womb, before being assumed by the Word.’ ” [St. Thomas Aquinas, Summa Theologica, III, Q. 33, A. 3. The work cited is now believed to have been written by Saint Fulgentius.]
4. It is contrary to the teaching of the Catholic Faith to claim that the soul of Jesus Christ was created before or after His body, or before or after His virgin conception, or before or after His Incarnation, or that the Incarnation occurred at a different time for His body than for His soul, or that His body or soul ever existed before the Incarnation, or apart from the Incarnation. For even after the death of Jesus Christ, and before His Resurrection, His Divine Nature remained always united, at all times, to His body and to His soul. [St. Thomas Aquinas, Summa Theologica, III, Q. 50, A. 2 and 3; he cites St. John of Damascus, De Fide Orthodoxa, III.]
5. It is contrary to the dogma of the Incarnation to claim that the creation of the body of Jesus Christ, and the creation of the soul of Jesus Christ, and the union of body and soul, and the Incarnation of the Divine Nature with His human nature, did not occur all in one and the same instant, at the moment of the Incarnation, which was the same as the moment of the virgin conception of the whole human nature of Jesus Christ.
6. In His human nature, Jesus is “like us in all respects except for sin,” and is “consubstantial with us in humanity.” Therefore, like the human nature of Christ, each human being is conceived such that body and soul are created in the same instant, and with body and soul united. The body is not created before the soul, nor is the soul created before the body; body and soul are created, as one human being, in the same instant. And the union of body and soul occurs at the same instant that both body and soul are created.
7. Therefore, what is true for Jesus in His humanity is also true for us in our humanity: the life of each human being, with body and soul united, begins at conception.
B. The Immaculate Conception of the Virgin Mary
1. The Blessed Virgin Mary was preserved free from all effects of original sin.
Pope Pius IX: “We declare, pronounce, and define that the doctrine which holds that the most Blessed Virgin Mary, in the first instant of her conception, by a singular grace and privilege granted by Almighty God, in view of the merits of Jesus Christ, the Savior of the human race, was preserved free from all stain of original sin, is a doctrine revealed by God and therefore to be believed firmly and constantly by all the faithful.” [Pope Pius IX, Ineffabilis Deus, the definition.]
2. Original sin effects both body and soul.
Council of Trent: “If any one does not confess that the first man, Adam, when he had transgressed the commandment of God in Paradise, immediately lost the holiness and justice wherein he had been constituted; and that he incurred, through the offence of that prevarication, the wrath and indignation of God, and consequently death, with which God had previously threatened him, and, together with death, captivity under his power who thenceforth had the empire of death, that is to say, the devil, and that the entire Adam, through that offence of prevarication, was changed, in body and soul, for the worse; let him be anathema.” [Council of Trent, Fifth Session, Decree on Original Sin, n. 1.]
Council of Trent: “If any one asserts, that the prevarication of Adam injured himself alone, and not his posterity; and that the holiness and justice, received of God, which he lost, he lost for himself alone, and not for us also; or that he, being defiled by the sin of disobedience, has only transfused death, and pains of the body, into the whole human race, but not sin also, which is the death of the soul; let him be anathema:–whereas he contradicts the apostle who says; By one man sin entered into the world, and by sin death, and so death passed upon all men, in whom all have sinned.” [Council of Trent, Fifth Session, Decree on Original Sin, n. 2.]
3. Therefore, the Virgin Mary was preserved free from the effects of original sin in both her body and her soul.
4. This preservation from all effects of original sin, in body and in soul, occurred in the first instant of her conception:
Pope Pius IX: “in the first instant of her conception [in primo instanti suae conceptionis] … preserved immune from every stain of original sin [ab omni originalis culpae labe praeservatam immunem]” [Pope Pius IX, Ineffabilis Deus, the definition; see footnote 29 for the Latin text.]
5. Therefore, the body and soul of the Virgin Mary were created at the same time, at her conception. If her soul were created before or after her body, or before or after her conception, then she would not have been preserved free from all effects of original sin, in body and in soul, in the first instant of her conception. The dogma of the Immaculate Conception requires us to believe that the body and soul of the Virgin Mary were created at the same time, and in the first instant of her conception.
6. Every single member of the human race is a human being composed of both a soul and a body:
Council of Ephesus: “In the same sort of way a human being, though he be composed of soul and body, is considered to be not dual, but rather one out of two.” [Council of Ephesus, Third Letter of Cyril to Nestorius, read into the acts of the Council.]
Pope Pius XII: “A marvelous vision, which makes us see the human race in the unity of one common origin in God ‘one God and Father of all, Who is above all, and through all, and in us all’ (Ephesians 4:6); in the unity of nature which in every man is equally composed of material body and spiritual, immortal soul….” [Pope Pius XII, Summi Pontificatus, n. 38.]
Pope Pius XII: “The soul is not a person, but the soul, joined to the body, is a person.” [Pope Pius XII, Munificentissimus Deus, n. 32.]
7. The Virgin Mary is a descendant of Adam and Eve, and a member of the human race. Her human nature, body and soul, is like the human nature of every member of the human race, and our human nature is like her human nature (except that she is sinless).
Second Vatican Council: “At the same time, however, because she belongs to the offspring of Adam she is one with all those who are to be saved.” [Second Vatican Council, Lumen Gentium, n. 53.]
Second Vatican Council: “Thus Mary, a daughter of Adam, consenting to the divine Word, became the mother of Jesus, the one and only Mediator.” [Second Vatican Council, Lumen Gentium, n. 56.]
Pope John Paul II: “The Second Vatican Council prepares us for this by presenting in its teaching the Mother of God in the mystery of Christ and of the Church. If it is true, as the Council itself proclaims, that ‘only in the mystery of the Incarnate Word does the mystery of man take on light,’ then this principle must be applied in a very particular way to that exceptional ‘daughter of the human race,’ that extraordinary ‘woman’ who became the Mother of Christ. Only in the mystery of Christ is her mystery fully made clear.” [Pope John Paul II, Redemptoris Mater, n. 4.]
Pope John Paul II: “Following tradition, the Council does not hesitate to call Mary ‘the Mother of Christ and mother of mankind’: since she belongs to the offspring of Adam, she is one with all human beings….” [Pope John Paul II, Redemptoris Mater, n. 23.]
8. Therefore, the Virgin Mary is also consubstantial with us in humanity and like us in all respects except for sin.
9. Therefore, what is true of the Virgin Mary is also true of us, the soul of each and every human being (i.e. each and every descendant of Adam and Eve) is created at the same instant as the body, which is the first instant of conception. If this were not true, then the Virgin Mary would not be like us in all respects except for sin, and she would not be “the offspring of Adam” and “one with all human beings.”
10. Therefore, every human being, beginning at the first instant of conception, is a human person, having both a body and a soul.
11. The first instant of conception is the single cell stage of development.
Sacred Congregation for the Doctrine of the Faith: “Thus the fruit of human generation, from the first moment of its existence, that is to say from the moment the zygote has formed, demands the unconditional respect that is morally due to the human being in his bodily and spiritual totality. The human being is to be respected and treated as a person from the moment of conception; and therefore from that same moment his rights as a person must be recognized, among which in the first place is the inviolable right of every innocent human being to life.” [Cardinal Ratzinger, CDF, Donum Vitae, I, 1. ]
Sacred Congregation for the Doctrine of the Faith: “The human being must be respected — as a person — from the very first instant of his existence.” [Ibid.]
12. Therefore, from the moment of conception, even when the human being is only a single cell, and at any time from conception to birth, the killing of a human being is the sin of abortion, which is a type of murder. For murder is the direct and voluntary killing of an innocent human being, and all human beings prior to birth are certainly innocent.
There should be no debate among the faithful about the time of ‘ensoulment’, or about when a prenatal becomes a human person. The dogmas of the Incarnation and of the Immaculate Conception necessarily imply that, in the very same instant, the body is created, and the soul is created, and body and soul are one. A human being, at any stage of life, in any condition whatsoever, has a body and a soul; every human being with a body and a soul is a human person. The soul in particular is made directly by God, in the image of God. Therefore, human life must be protected from the moment of conception. All prenatal human beings are innocent human persons created by God and in the image of God.
The above article is an excerpt from my book: