"The declared enemies of God and His Church, heretics and schismatics, must be criticized as much as possible, as long as truth is not denied. It is a work of charity to shout: 'Here is the wolf!' when it enters the flock or anywhere else."
St. Francis de Sales, Introduction to the Devout Life, Part III, Chapter 29

"In such a crux there remains the historical truth: that this our European structure, built upon the noble foundations of classical antiquity, was formed through, exists by, is consonant to, and will stand only in the mold of, the Catholic Church. Europe will return to the Faith, or she will perish."
Hilaire Belloc, Europe and the Faith

"We have often considered and admired the noble gifts of your nation which enable the American people to be alive to every good work which promotes the good of humanity and the splendor of civilization."
Pope Leo XIII, Testem Benevolentiae Nostrae

"If the enemies of the truth never have enough of blaspheming our Benefactor, we must be all the more tireless in praising the God of all."
St. John Chrysostom, Adversus Iudaeos

"In times of desolation, God conceals Himself from us so that we can discover for ourselves what we are without Him."
St. Margaret of Cortona

"Who is there so demented, who, though not able to overtake, does not at least earnestly desire to follow those whom no force could deter from defending the faith of their ancestors, no threats, no blandishments, not life, not death, not the palace, not the Imperial Guards, not the Emperor, not the empire itself, not men, not demons?— whom, I say, as a recompense for their steadfastness in adhering to religious antiquity, the Lord counted worthy of so great a reward, that by their instrumentality He restored churches which had been destroyed, quickened with new life peoples who were spiritually dead, replaced on the heads of priests the crowns which had been torn from them, washed out those abominable, I will not say letters, but blotches of novel impiety, with a fountain of believing tears, which God opened in the hearts of the bishops?"
St. Vincent of Lérins, Commonitory for the Antiquity and Universality of the Catholic Faith Against the Profane Novelties of All Heresies V.xiii

“This is no time for believing everyone, believe only those whom you see modeling their lives on the life of Christ. Endeavor always to have a good conscience; practice humility; despise all worldly things; and believe firmly in the teaching of our Holy Mother Church."
St. Teresa of Avila, The Way of Perfection

“People hate the truth for the sake of whatever it is that they love more than the truth. They love truth when it shines warmly on them and hate it when it rebukes them.”
St. Augustine of Hippo, Confessions, Book 10, ch. 23

"To be deep in history is to cease to be a Protestant."

St. John Henry Newman, An Essay on the Development of Christian Doctrine, Introduction, pt 5

"Those rabid dogs barking against Christ; let their followers learn—those who think that the church has had no philosophers, no orators, no men of learning; let them learn the number and quality of the men who founded, built, and adorned the church and let them stop accusing our faith of such rustic simplicity, and recognize instead their own ignorance."

St. Jerome, On Illustrious Men, Preface, paragraph 7

“There is no evil to be faced that Christ does not face with us. There is no enemy that Christ has not already conquered. There is no cross to bear that Christ has not already born for us, and does not now bear with us.”

Pope St. John Paul II

"I have never spared heretics, and have endeavored in every possible manner to make the enemies of the Church my own enemies."

St. Jerome, The Dialogue Against the Pelagians, Preface, paragraph 2

"You cannot be half a saint; you must be a whole saint or no saint at all."

St. Therese of Lisieux, Letter to Abbe Belliere, June 21, 1897

"Sanctify yourself and you will sanctify society."

St. Francis of Assisi

"It is a characteristic of any decaying civilization that the great masses of the people are unaware of the tragedy. Humanity in a crisis is generally insensitive to the gravity of the times in which it lives. Men do not want to believe their own times are wicked, partly because they have no standard outside of themselves by which to measure their times. If there is no fixed concept of justice, how shall men know it is violated? Only those who live by faith really know what is happening in the world; the great masses without faith are unconscious of the destructive processes going on, because they have lost the vision of the heights from which they have fallen."

Ven. Fulton J. Sheen, Communism and the Conscience of the West

"Hold firmly that our faith is identical with that of the ancients. Deny this, and you dissolve the unity of the Church."

St. Thomas Aquinas, Questiones Disputatae de Veritate, Question 14, Article 12.

"And so, lastly, does the very name of "Catholic", which, not without reason, amid so many heresies, the Church has thus retained; so that, though all heretics wish to be called Catholics, yet when a stranger asks where the Catholic Church meets, no heretic will venture to point to his own chapel or house."

St. Augustine of Hippo, Against the Fundamental Epistle of Manichaeus, Chapter 4

"Ever since the days of Adam, man has been hiding from God and saying, 'God is hard to find."

Ven. Fulton Sheen, Peace of Soul

"If it is dangerous to be negligent in steering a ship in the midst of the sea, how much more perilous to abandon it in a storm with the waves running high; and even so the Church which makes its way through the ocean of this world like a great ship, buffeted in this life by diverse waves of temptation, is yet not to be abandoned."

St. Boniface, Epistle to Archbishop Cuthbert of Canterbury VIII