Catechism of the Catholic Church §587 — excerpt
If the Law and the Jerusalem Temple could be occasions of opposition to Jesus by Israel's religious authorities, his role in the redemption of sins, the divine work par excellence, was the true stumbling-block for them.
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.