Catechism of the Catholic Church §622 — excerpt
The redemption won by Christ consists in this, that he came "to give his life as a ransom for many" (Mt 20:28), that is, he "loved [his own] to the end" (Jn 13:1), so that they might be "ransomed from the futile ways inherited from [their] fathers" (I Pt 1:18).
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.