After original sin, God still called man and even promised a victory. He announced that there would be a Messiah and Redeemer, a battle between the serpent and the Woman, and the final victory for her descendents: "I will put an enmity between you and the woman and between your offspring and hers, he will strike at your head while you strike at his heel" (Gen 3:15).
This passage announces Christ as the "New Adam" who superabundantly makes amends for Adam's sin. Many church Fathers see Mary as the "new Eve," the first to benefit from Christ's redemption by her Immaculate Conception and freedom from all personal sins.
Ref. CCC 410-411
Taken From The Compendium - Catechism Of The Catholic ChurchRead More
At the Last Supper with his apostles on the eve of his passion Jesus anticipated, that is, both symbolized his free self-offering and made it really present: “This is my Body which is given for you” (Luke 22:19), “This is my Blood which is poured out...” (Matthew 26:28) Thus he both instituted the Eucharist as the “memorial” (1 Corinthians 11:25) of his sacrifice and instituted his apostles as priests of the new covenant. Please click here to learn more about Holy Mass, also known as the celebration of the Holy Eucharist.