66 Are we to say that this prayer went unheeded by the heavenly Father, who yet accepted the sacrifice of Christ's blood on the Cross? Did not Christ say that His Father never failed to hear Him? (60) He prayed for the Church; He sacrificed Himself on the Cross for it, and promised it His unfailing presence. Assuredly, then, we must believe that this Church has always been, and still is, one, holy, catholic and apostolic; for thus was it founded.
Source: Aeterna Dei Sapientia (Vatican.va)