PROOF FROM SCRIPTURE
Genesis 3:15
No direct or categorical and stringent proof of the dogma can be brought forward from Scripture. But the first scriptural passage which contains the promise of the redemption, mentions also the Mother of the Redeemer. The sentence against the first parents was accompanied by the Earliest Gospel (Proto-evangelium), which put enmity between the serpent and the woman:
"and I will put enmity between thee and the woman and her seed; she (he) shall crush thy head and thou shalt lie in wait for her (his) heel" (Genesis 3:15). The translation "she" of the Vulgate is interpretative; it originated after the fourth century, and cannot be defended critically. The conqueror from the seed of the woman, who should crush the serpent's head, is Christ; the woman at enmity with the serpent is Mary. God puts enmity between her and Satan in the same manner and measure, as there is enmity between Christ and the seed of the serpent. Mary was ever to be in that exalted state of soul which the serpent had destroyed in man, i.e. in sanctifying grace. Only the continual union of Mary with grace explains sufficiently the enmity between her and Satan. The Proto-evangelium, therefore, in the original text contains a direct promise of the Redeemer, and in conjunction therewith the manifestation of the masterpiece of His Redemption, the perfect preservation of His virginal Mother from original sin.
PROOF FROM TRADITION
In regard to the sinlessness of Mary the older Fathers are very cautious: some of them even seem to have been in error on this matter.
Origen, although he ascribed to Mary high spiritual prerogatives, thought that, at the time of Christ's passion, the sword of disbelief pierced Mary's soul; that she was struck by the poniard of doubt; and that for her sins also Christ died (Origen, "In Luc. hom. xvii").
In the same manner St. Basil writes in the fourth century: he sees in the sword, of which Simeon speaks, the doubt which pierced Mary's soul (Epistle 259).
St. Chrysostom accuses her of ambition, and of putting herself forward unduly when she sought to speak to Jesus at Capharnaum (Matthew 11:46; Chrysostom, Hom. xliv; cf. also "In Matt.", hom. iv).
But these stray private opinions merely serve to show that theology is a progressive science. If we were to attempt to set forth the full doctrine of the Fathers on the sanctity of the Blessed Virgin, which includes particularly the implicit belief in the immaculateness of her conception, we should be forced to transcribe a multitude of passages. In the testimony of the Fathers two points are insisted upon: her absolute purity and her position as the second Eve (cf. I Cor. 15:22).
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