14 It follows after commendation of the Trinity, “The Holy Church.” God is pointed out, and His temple. “For the temple of God is holy,” says the Apostle, “which (temple) are you.” This same is the holy Church, the one Church, the true Church, the catholic Church, fighting against all heresies: fight, it can: be fought down, it cannot. As for heresies, they went all out of it, like as unprofitable branches pruned from the vine: but itself abides in its root, in its Vine, in its charity. “The gates of hell shall not prevail against it.”
Source: On the Creed: A Sermon to Catechumens (New Advent)