[topcat54]

This being the case, ever since the time when by one man sin thus entered into this world and death by sin, and so it passed through to all men, up to the end of this carnal generation and perishing world, the children of which beget and are begotten,there never has existed, nor ever will exist, a human being of whom, placed in this life of ours, it could be said that he had no sin at all, with the exception of the one Mediator, who reconciles us to our Maker through the forgiveness of sins. (Augustine)

For wholly alone of those born of woman was our Holy Lord Jesus, Who by the strangeness of His undefiled Birth has not suffered the pollutions of earthly corruption, but dispelled them by heavenly majesty. (Ambrose)

Quoted here

[vladimir998]

"Now with the exception of the holy Virgin Mary in regard to whom, out of respect for the Lord, I do not propose to have a single question raised on the subject of sin -- after all, how do we know what greater degree of grace for a complete victory over sin was conferred on her who merited to conceive and bring forth Him who all admit was without sin -- to repeat then: with the exception of this Virgin, if we could bring together into one place all those holy men and women, while they lived here, and ask them whether they were without sin, what are we to suppose that they would have replied?" (St. Augustine, De natura et gratia PL 44:267, from Carol Mariology, volume 1, page 15)