Catechism of the Catholic Church §42 — excerpt
God transcends all creatures. We must therefore continually purify our language of everything in it that is limited, imagebound or imperfect, if we are not to confuse our image of God --"the inexpressible, the incomprehensible, the invisible, the ungraspable"-- with our human representations.
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.
Also cites: Liturgy of St. John Chrysostom, Anaphora