Catechism of the Catholic Church §1725 — excerpt
The Beatitudes take up and fulfill God's promises from Abraham on by ordering them to the Kingdom of heaven. They respond to the desire for happiness that God has placed in the human heart.
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.