It is at the moment of the fusion of the male and female gametes that the body of the unique human individual is formed. This moment of the formation of the progenitor cell, is the moment that God breathes of his own Spirit into the 'body', and the moment the new being becomes a unique living human person (soul).
And God said: "Let us make man to our own image... and...to the image of God He created him: male and female He created them." "He formed man of the earth: and breathed into his face the breath of life, and man became a living soul." (Genesis 1:26-27; 2:7)
"The unity of the body and soul is so profound that one has to consider the soul to be the 'form' of the body: ie. it is because of its spiritual soul that the body made of matter becomes a living human body; spirit and matter in man, are not two natures united, but rather their union forms a single nature." *(CCC 365)
Sadly, the first parents of humanity, Adam and Eve, were tempted in the freedom of their hearts to abandon their trust in God, thinking they could be "like Him"(Genesis 3:5) and sufficient in themselves to live independent of Him. Prior to their act of disobedience their life had been a life of holy trust and obedience, created in holy innocence with their spiritual souls presiding in perfect harmony over their physical faculties in the perfectly ordered environment of their garden paradise called Eden.
God had warned them, to disobey Him would mean their deaths. They sinned, and were afraid. Disorder and death entered their world just as God had said it would. Their paradise became a harsh environ. They now would have to work in order to partake of its fruits. There was now disharmony in their own selves, with their spiritual souls struggling to maintain control over their bodies, and these same wounds they now experienced in themselves they found to be equally present in the lives of their children. Their sin had likewise mortally wounded the nature of all who would be born of them through all the generations to come.
But God did not abandon them entirely. He promised He would come Himself to save them. To the Devil He had said, "I will put enmity between thee and the woman." And through His prophet Isaiah he said, "A woman, a virgin shall conceive and bear a son, and His name shall be called Emmanuel, ('God with us'). He shall be called 'God the Mighty' and 'Father of the world to come'. God Himself will come and save you." (Isaiah 7:14; 9:6; 35:4; Matthew 1:23)
The Saviour came in His time. He taught that in the Great Mystery of God's own Life and Being is the Presence of, not one, but THREE PERSONS Who are together called the Holy Trinity, One God, Whose Nature, Life and Essence, is truly One Being; divisible only in persons, but not divisible in the one Life and Being they share in unison, as one. This is the great mystery of the One Life Which is the Father, the Son and the Holy Spirit. Truly, God has come to save us all.
So, this is the wounded nature of our lives and how we have come to inherit it as children of Adam and Eve, our first parents. Our nature is disordered and we all must experience the death which the disorder of sin has brought to us all.
We have not, however, been abandoned by our loving God and Father. He is constantly working to bring goodness out of all the evil, sin and death which is operating in our wounded world. The 'particular' goodness He wants is 'love'. And this particular goodness, like pure gold, is tested and tried and refined in a fire. The fire is the fire of suffering which tests our courage and enduring trust and faithfulness. It is also the fire of temptation, for temptation tries loyalty and integrity and steadfastness in the love for only what is truly good and just and right. And by these we learn to discern and test and know that we are, in all things, always to choose only that which is truly right and good. And in choosing only these things, we come to show ourselves to be truly the children of our Father in Heaven.
So, we can see there is very real purpose at work in all the situations and troubles we face. We see all the beautiful innocents being born into the world. They haven't sinned. But they have inherited a wounded nature; a nature wounded by sin. In that nature all of their hearts are to be formed; free hearts which will come to learn the wonder of what it is to exist midst all of the temptations, sufferings and joys of this life. All of these hearts will learn to distinguish between the consequences of all the powers and influences at work in our wounded world. Though wounded in their nature, and in the face of great stresses, trials and temptations, all of their experiences will always encourage them to learn only to seek and to know and to do and to love only what is right and good. In this way is each heart formed and tested. In this way each heart, by its own choice, shall come to choose its own destiny. For, as the Scripture says: "Before man is fire and water,...life and death, good and evil; that which a man chooses shall be given to him." (Ecclesiasticus 15:17-18)
So, born as we are into this wounded world, don't be surprised or frightened by temptations in whatever form they come. They are not you. They are no fault of yours. Your wounded nature is not your fault either. This wounded world is not your fault. The fault becomes our fault only when, and if, we give in to a temptation and make it our own. Remember the Lord's Prayer? "Father.......lead us; not into temptation, but deliver us...from evil..."
Also remember: and never be discouraged, it seems that no matter how hard we might wish or try never to sin; in our wounded state, at some time, the call to sin will have its way with us, because the Scripture always speaks truly, and it tells us, "The man who says he is without sin, is a liar." (1 John 8-10) So, the problem for us, then, is not that we have sinned, but whether we shall persist in our sin/s, for in this shall our hearts be proven. From the good heart always wells up sorrow and repentance and desire for reconciliation. Forgiveness always awaits him/her. Fear not your fall/s. Love God and persevere in your love. The joys of heaven await you.
Read also: Romans 8:18-30.
* CCC is Catechism of the Catholic Church