Catechism of the Catholic Church §713 — excerpt
The Messiah's characteristics are revealed above all in the "Servant songs." These songs proclaim the meaning of Jesus' Passion and show how he will pour out the Holy Spirit to give life to the many: not as an outsider, but by embracing our "form as slave."
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.