That is why the doctrine of the Immaculate Conception, which we celebrate today, becomes a very important one. It reminds us that Mary's sinlessness is not something that Mary achieved by her own power. It is a gift of God, given to her right from the very moment of her conception. It is in the genes, as they say. In the same vein, those of us who happen to be holy, who sin less than the average sinner, should regard our holiness as basically a gift of God and not an achievement. Our attitude should then be characterised by two basic attitudes, thankfulness to God, and humility before those who are naturally and spiritually less gifted than we are.
The dogma of the Immaculate Conception of Mary was defined by Pope Pius IX in 1854. It affirms the belief that the Blessed Virgin Mary was free from sin right from the very beginning of her life. That means that by the grace of God, she was shielded from original sin which all humankind inherit at the very moment they begin to live, i.e. at the moment they are conceived in their mother's womb. That means that Mary was not burdened with a defective human nature with which you and I come into the world. She came into the world with a perfect human nature like that of Eve and Adam before they sinned and fell from grace. God gave her this perfect human nature not as a reward for anything she did, not on account of any merit on her part, but in view of the singular role she was to play in life, namely, that of being the mother of God's Son. The doctrine of the Immaculate Conception tells us something about who Mary is. But maybe it tells us more about who God is and who we are in light of God's providential love.
Belief in the Immaculate Conception of Mary is belief in a provident God, i.e., a God who provides for the future, who prepares His children for their assigned task in life even before they are born, a God who foresees and equips us with all the natural and supernatural qualities we need to play our assigned role in the drama of human salvation. God anoints them already in the womb those men and women whom He created to be His prophets. As He told Jeremiah, "Before I formed you in the womb I knew you, and before you were born I consecrated you; I appointed you a prophet to the nations" (Jeremiah 1:5). God does not just throw us into this world wide wilderness and then leave us to fight it out among ourselves. The theory of evolution with its doctrine of the survival of the fittest may describe human nature in its fallen state, in the state of original sin, it does not describe life for the people of God redeemed by grace from the unbridled effects of the Fall.
As we rejoice with Mary, God's most favoured one ("full of grace") on the feast of her conception, let us thank God for His love and mercy which embraces us right from the moment of our own conception. As Scripture says, "For who makes you different from anyone else? What do you have that you did not receive? And if you did receive it, why do you boast as though you did not?" (1Corinthians 4:7). Everything is gift, everything good in us is God's grace. For we all, children of God, are also favoured ones and heirs of God's grace. Yet Mary remains the most favoured one, the mother of all favoured ones, the one that enjoys the fullness of grace. (Fr. Munachi)