The doctrine of Mary's Immaculate Conception does not refer to Mary's parents, but it has reference to Mary Herself. It means that Mary was free from sin from the moment of her conception, at no time was sin ever on her soul.

John the Baptist received this grace three months before his birth, namely at the time when Mary visited his mother, St. Elizabeth. But he was not immaculate conceived, for it had been six months since his conception when that grace came to him. But where Mary is concerned, God's grace came to her at the very moment of her creation.

In the first beginnings of the world, we are told that God looked upon the work of His hands and "saw that it was good." The morning star praised God as it is written: "The morning stars praised me together" (Job 38,7), for the irrational works of God offer praises to Him, and they offer it in their undeviating courses and their exact fulfillment of the law imposed upon them. The planets move in their orbits around the sun; the stars keep their fixed courses; the earth fulfills it own natural functions. Seed time and harvest; summer and winter; night and day, these all follow one another in unvarying sequence, and all offer the worship of obedience to God.

But when sin came into the world, the shadow of God's displeasure fell upon all things beautiful, and sin and death passed down from generation to generation. But the gloom of history of sin and rebellion was relieved by one point of brightness. Human nature had formed a wicked alliance with Satan. In one instance however, a partnership between man and Satan was destined to be prevented.

The first Eve was chosen by Satan as his ally for the disfigurement of God's greatest designs. Mary, the second Eve, was chosen by God to be the enemy of Satan. The second Eve would maintain an opposing war with Satan and his seed. There would be a unity of cause between Mary and her seed against Satan and his seed. The divine work of Redemption was destined to be the counterpart of the spiritual destruction wrought by Adam and Eve.

In the early morning of her life, the first moment of her being, Mary is shielded from sin, and what is more, she is filled with a plenitude of grace. And the Psalmist cried out with truth (45.5): "The Most High has sanctified His own Tabernacle."

True, together with the whole race, Mary was included in Adam's sentence, but for the sake of Him Who upon the Cross was going to redeem Mary and us, grace was given to Mary anticipation. Mary could not merit the restoration of that grace, but the grace was bestowed upon her by God's free bounty from the first moment of her existence. And so, Mary never came under the curse of original sin which consisted in the loss of grace.

This special privilege of grace fitted Mary to become the Mother of our Redeemer; to receive Him into her bosom. Mary grew in grace, and so much so that when the angel came to he to announce the approach of the Incarnation, she was already full of grace. Although it was only after many years of its existence that the Catholic Church set at rest the question of Mary's Immaculate Conception, yet God's revelation of this dogma dates from a very early period after the creation of Adam and Eve. God Himself proclaimed this when He spoke of the enmity that He was going to place between Mary and Satan. " I will place enmities between thee and the woman, between thy seed and her seed."

God had promised that Satan would not gain entrance into the garden of Mary's soul. Mary's body would be a spotless paradise of virgin earth out of which God Himself would form a body for His beloved Son. True, Mary's parents were conceived in sin, but not so Mary, for she would be conceived without any spot of sin.

Here is a simple illustration showing that it is God's grace which kept original sin from disfiguring the soul of Mary and that it is also God's grace that wipes away original sin from our souls.

Take the case of two poor families. In the first family a child has been born, and as we might expect, born in poverty.  A wealthy and generous person comes along and gives that poor baby a cheque for $100-000 . The baby then becomes rich. In the second poor family, a baby is about to be born, and in normal circumstance it would be born poor. But again, a wealthy person comes along with a cheque for $100-000, and before the baby is actually born, it is presented with the cheque. You can see what happens. The baby is born wealthy. At no time has the mark of poverty been upon the baby, As it were, the wealthy person got in first.

So this is the difference: In the first case there was poverty, which was than wiped out. In the second case, poverty was prevented from coming onto the child. In both cases it was because of the wealthy person. At no future date would any unkind person be able to throw it up at the second child that once upon a time it had been in poverty.

When Mary was conceived in the womb of her mother Anne, at that same moment grace (spiritual wealth) was poured into her soul. Original sin was not permitted to be on her soul. Mary's soul always had grace on it. God got in first, as it were.

Let us say with intense fervor, "Queen conceived without Original Sin, pray for us."

Source: Fr. P.J. Gearon.