CCC 173

"Indeed, the Church, though scattered throughout the whole world, even to the ends of the earth, having received the faith from the apostles and their disciples. . . guards [this preaching and faith] with care, as dwelling in but a single house, and similarly believes as if having but one soul and a single heart, and preaches, teaches and hands on this faith with a unanimous voice, as if possessing only one mouth."⁵⁹ St. Irenaeus, Adv. haeres. I, 10, 1-2: PG 7PG — Patrologia Graeca (Migne)/1, 549-552.