How the Church knows the faith — the place of Holy Scripture and of the tradition handed down from the apostles. The Fathers appeal to both together, and the East holds Scripture and Tradition alike; the Reformation's sola scriptura made Scripture the sole rule, and the Council of Trent (Session IV, 1546) received Scripture and the unwritten traditions with equal reverence. Sources span the Fathers to the Reformation; traditions are badged, never refereed.
3 Patristic · 1 Catholic · 1 Anglican · 1 Lutheran · 1 Reformed · 1 Orthodox
“All scripture, inspired of God, is profitable to teach, to reprove, to correct, to instruct in justice,”
“Now our Lord Jesus Christ himself, and God and our Father, who hath loved us, and hath given us everlasting consolation, and good hope in grace,”
“For leaving the commandment of God, you hold the tradition of men, the washing of pots and of cups: and many other things you do like to these.”
“We have learned from none others the plan of our salvation, than from those through whom the Gospel has come down to us, which they did at one time proclaim in public, and, at a later period, by the will of God, handed down to us in the Scriptures, to be the ground and pillar of our faith.”
“Of the beliefs and practices… which are preserved in the Church, some we possess derived from written teaching; others we have received delivered to us in a mystery by the tradition of the apostles; and both of these in relation to true religion have the same force.”
“In the Catholic Church itself, all possible care must be taken, that we hold that faith which has been believed everywhere, always, by all.”
At the Diet of Worms, Martin Luther refused to recant his writings, declaring that unless he were convinced by the testimony of Scripture and plain reason his conscience was captive to the Word of God — the founding moment of the Reformation's sola scriptura.
Trent opens. Over eighteen years and five popes it answers the Reformers point by point — on Scripture and tradition, justification, the sacraments, the Eucharist, purgatory and the saints.
“receives and venerates with an equal affection of piety, and reverence, all the books both of the Old and of the New Testament… as also the said traditions, as well those appertaining to faith as to morals.”
“Holy Scripture containeth all things necessary to salvation: so that whatsoever is not read therein, nor may be proved thereby, is not to be required of any man, that it should be believed as an article of the Faith, or be thought requisite or necessary to salvation.”
“We believe, teach, and confess that the sole rule and standard according to which all dogmas together with all teachers should be estimated and judged are the prophetic and apostolic Scriptures of the Old and of the New Testament alone.”
“The whole counsel of God concerning all things necessary for his own glory, man's salvation, faith and life, is either expressly set down in Scripture, or by good and necessary consequence may be deduced from Scripture: unto which nothing at any time is to be added, whether by new revelations of the Spirit, or traditions of men.”
“By the name holy tradition is meant the doctrine of the faith, the law of God, the sacraments, and the ritual, as handed down… from one to another, and from generation to generation.”
“The same holy Mother Church holds and teaches that God, the beginning and end of all things, may be certainly known by the natural light of human reason, by means of created things; 'for the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made,' but that it pleased his wisdom and bounty to reveal himself, and the eternal decrees of his will, to mankind by another and a supernatural way : as the Apostle says, ' God, having spoken on divers occasions, and many ways, in times past, to the Fathers by the Prophets; last of all, in these days, hath spoken to us by his Son.' It is to be ascribed to this divine revelation, that such truths among things divine as of themselves are not beyond human reason, can, even in the present condition of mankind, be known by every one with facility, with firm assurance, and with no admixture of error.”
The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.