Catechism of the Catholic Church §335 — excerpt
In her liturgy, the Church joins with the angels to adore the thrice-holy God. She invokes their assistance (in the Roman Canon's Supplices te rogamus.
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.