Here's the ammo, trads...
St Thomas Aquinas
“It is absurd, and a detestable shame, that we should suffer those traditions to be changed which we have received from the fathers of old." - The Decretals (Dist. xii, 5) Cited by St Thomas Aquinas in the Summa Theologica, II, I, Q. 97, art. 2.
"'One faith,' St. Paul writes (Eph. 4:5). Hold most firmly that our faith is identical with that of the ancients. Deny this, and you dissolve the unity of the Church ... We must hold this for certain, namely: that the faith of the people at the present day is one with the faith of the people in past centuries. Were this not true, then we would be in a different church than they were in and, literally, the Church would not be One."
"As I said before, the Church, having received this preaching and this faith, although she is disseminated throughout the whole world, yet guarded it, as if she occupied but one house. She likewise believes these things just as if she had but one soul and one and the same heart; and harmoniously she proclaims them and teaches them and hands them down, as if she possessed but one mouth. For, while the languages of the world are diverse, nevertheless, the authority of the tradition is one and the same" – St Irenaeus, Against Heresies, 1:10:2, 189 AD.
“The best advice that I can give you is this. Church traditions – especially when they do not run counter to the Faith – are to be observed in the form in which previous generations have handed them down.” - St Jerome, Letters, 71, 6. (4th Century).
"Although there are many who believe that they themselves hold to the teachings of Christ, there are yet some among them who think differently from their predecessors. The teaching of the Church has indeed been handed down through an order of succession from the apostles and remains in the churches even to the present time. That alone is to be believed as the truth which is in no way at variance with ecclesiastical and apostolic tradition" – Origen, The Fundamental Doctrines, 1:2, 225 AD.
Pope St Leo the Great
"Teach nothing new, but implant in the hearts of everyone those things which the fathers of venerable memory taught with a uniform preaching ... Whence, we preach nothing except what we have received from our forefathers. In all things, therefore, both in the rule of faith in the observance of discipline, let the pattern of antiquity be observed." - Pope St Leo the Great, Father and Doctor of the Church.
Pope Leo XIII
"They knew only too well the intimate bond which unites faith with worship, 'the law of belief with the law of prayer,' and so, under the pretext of restoring it to its primitive form, they corrupted the order of the liturgy in many respects to adapt it to the errors of the Innovators." - Pope Leo XIII, Apostolicae Curae, September 13, 1896.
Pope St Pius X
"But for Catholics nothing will remove the authority of the second Council of Nicea, where it condemns those 'who dare, after the impious fashion of heretics, to deride the ecclesiastical traditions, to invent novelties of some kind . . . or endeavour by malice or craft to overthrow any one of the legitimate traditions of the Catholic Church'. . . . Wherefore the Roman Pontiffs, Pius IV and Pius IX, ordered the insertion in the profession of faith of the following declaration: 'I most firmly admit and embrace the apostolic and ecclesiastical traditions and other observances and constitutions of the Church'.” - Pope St Pius X, Pascendi Dominici Gregis (Encyclical Against Modernism.
"The true friends of the people are neither revolutionaries nor innovators, but traditionalists." - Pope St Pius X, Notre Charge Apostolique.
Second Council of Nicea (Seventh Ecumenical Council)
"If anyone rejects any written or unwritten tradition of the Church, let him be anathema."
"Let everything that conflicts with ecclesiastical tradition and teaching, and that has been innovated and done contrary to the examples outlined by the saints and the venerable Fathers, or that shall hereafter at any time be done in such a fashion, be anathema."
Pope Pius XII
"The day the Church abandons Her universal tongue will be the day before She returns to the Catacombs." - Pope Pius XII (a few days before his death).
Pope Paul VI
"We would warn against the danger and damage of the blind rejection of the inheritance which the past, through a wise and selective tradition, transmits to new generations. If we did not hold this transmission in proper regard we could lose the treasure accrued by civilization.” - October 29, 1972.
"But in regard to those observances which we carefully attend and which the whole world keeps, and which derive not from Scripture but from Tradition, we are given to understand that they are recommended and ordained to be kept, either by the apostles themselves or by plenary [ecumenical] councils, the authority of which is vital to the Church.” – St Augustine, Letter to Januarius, 400 AD.
St Simeon of Thessalonica
"With love, we pass on to you that which we have taken from the Fathers, for we offer nothing new, but only that which has been passed on to us, and we have changed nothing but we have retained everything, like a creed, in the state in which it has been given to us. We worship exactly as Christ Himself did and as did the Apostles and the Fathers of the Church." - St Simeon of Thessalonica, in Migne, Patrologia Graeca, 155:701 a-b.
"Therefore, heresy is from the Greek word meaning 'choice' . . . . But we are not permitted to believe whatever we choose, nor to choose whatever someone else has believed. We have the Apostles of God as authorities, who did not . . . choose what they would believe but faithfully transmitted the teachings of Christ. So, even if an angel from heaven should preach otherwise, he shall be called anathema. - St Isidore, Doctor of the Church and last of the great Latin Fathers, Etymologies, 7th Century.
"You are fortunate, you have remained in the Church through your faith. You held fast to the foundations of the faith which has come down to you from Apostolic Tradition. . . .In the present crisis, it is they who have broken away from it." - St Athanasius, Doctor of the Church, died 373 AD.
"But you are blessed, who by faith are in the Church, dwell upon the foundations of the faith, and have full satisfaction, even the highest degree of faith which remains among you unshaken. For it has come down to you from apostolic tradition, and frequently accursed envy has wished to unsettle it, but has not been able" – St Athanasius, Festal Letters 29, 330 AD.
St Vincent of Lerins
"What then shall the Catholic do if some portion of the Church detaches itself from communion of the universal Faith? What other choice can he make -- and if some new contagion attempts to poison, no longer a small part of the Church, but the whole Church at once, then his great concern will be to attach himself to antiquity (Tradition) which can no longer be led astray by any lying novelty."
"The Church of Christ, zealous and cautious guardian of the dogmas deposited with it, never changes any phrase of them. It does not diminish them or add to them; it neither trims what seems necessary now grafts things superfluous . . . but it devotes all its diligence to one aim: To treat tradition faithfully and wisely; to consolidate and to strengthen what already was clear; and to guard what already was confirmed and defined." - St Vincent of Lerins, Commonitoria (5th Century).
“With great zeal and closest attention, therefore, I frequently inquired of many men, eminent for their holiness and doctrine, how I might, in a concise and, so to speak, general and ordinary way, distinguish the truth of the Catholic faith from the falsehood of heretical depravity. I received almost always the same answer from all of them—that if I or anyone else wanted to expose the frauds and escape the snares of the heretics who rise up, and to remain intact and in sound faith, it would be necessary, with the help of the Lord, to fortify that faith in a twofold manner: first, of course, by the authority of divine law [Scripture] and then by the tradition of the Catholic Church.” – St Vincent of Lerins, The Notebooks, 434 AD.
Blessed John Henry, Cardinal Newman
"It is quite evident that this passage furnishes no argument whatever that the sacred Scripture, without Tradition, is the sole rule of faith; for, although sacred Scripture is profitable for these four ends, still it is not said to be sufficient. The Apostle [Paul] requires the aid of Tradition (2 Thess. 2:15). Moreover, the Apostle here refers to the scriptures which Timothy was taught in his infancy.”
St Peter Canisius
"Better that only a few Catholics should be left, staunch and sincere in their religion, than that they should, remaining many, desire as it were, to be in collusion with the Church's enemies and in conformity with the open foes of our faith." - St Peter Canisius (1521-1597)
“It behoves us unanimously and inviolably to observe the ecclesiastical traditions, whether codified or simply retained by the customary practice of the Church.” – St Peter Canisius (1521-1597)
What could be clearer? Abandon tradition at your spiritual peril...