It is but fit that the Blessed Virgin should be without any stain, and that she should so entirely conquer Satan, that she was not even for one moment subject to him. If Mary's soul had been, only for one moment, spotted with original sin, she would have been subject to Satan for that length of time; she would have been a seat, a dwelling of the devil, a slave to him, and a child of divine wrath. Would it have been suitable that the only Son of God should dwell nine months in the womb of a created being, who before, though for ever so short a space of time had been a dwelling of Satan?
Can we think, without trembling, that she, who was chosen from all eternity to become the mother of our Lord, had been a slave to the devil, an object of divine wrath? If this had been the case, Satan could have boasted that, before Christ, he had inhabited the Ark which was destined by the Almighty, not to preserve manna, or the lifeless tables of the law, but to keep, during nine months, the holy Lawgiver Himself. Would this have been worthy of Christ? No one will dare say it. Hence, the honor of Him, whom Mary gave to the world, demands that she should have been conceived immaculate. The high dignity to which Mary was raised allows not the thought that she, even for one moment, was defiled with original sin.
(Lives of the Saints, Francis Xavier Weninger, 1876).
Can we think, without trembling, that she, who was chosen from all eternity to become the mother of our Lord, had been a slave to the devil, an object of divine wrath? If this had been the case, Satan could have boasted that, before Christ, he had inhabited the Ark which was destined by the Almighty, not to preserve manna, or the lifeless tables of the law, but to keep, during nine months, the holy Lawgiver Himself. Would this have been worthy of Christ? No one will dare say it. Hence, the honor of Him, whom Mary gave to the world, demands that she should have been conceived immaculate. The high dignity to which Mary was raised allows not the thought that she, even for one moment, was defiled with original sin.
(Lives of the Saints, Francis Xavier Weninger, 1876).