I think that it is big problem when we are looking for culprit outside of ourselves. It is much easier to see every mistake or sin as someone else’s responsibility and see ourselves as victims of “circumstances”.
The stain of original sin is that the person does not have the state of sanctifying grace at conception, even though there is no personal sin present. The reason there was no original sin in Jesus Christ is his divine nature. The reason there was no original sin in the Virgin Mary is that she was conceived with sanctifying grace, that is, preserved from the stain of original sin.
Mary is the antithesis to Eve. Eve allowed herself to be subject to Satan. Eve introduced evil to humanity, through Adam. Mary introduced salvation to humanity, through Jesus.
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