1. Apostolic Succession  [C]oncerning matters of faith, they [The Fathers at Nicea] did not write: ‘It was decided,’ but ‘Thus the Catholic Church believes.’ . . . in order to show that their judgement was not of more recent origin, but was in fact Apostolic times; and that what they wrote was no discovery of their own, but is simply that which was taught by the apostles. (On the Councils of Ariminum and Seleucia 5; NPNF 2, Vol. IV)

It appeared desirable to adhere to and maintain to the end, that faith which, enduring from antiquity, we have received as preached by the prophets, the Gospels, and the Apostles . . . (On the Councils of Ariminum and Seleucia 10; NPNF 2, Vol. IV)

For, what our Fathers have delivered, this is truly doctrine; . . . to confess the same thing with each other, and to vary neither from themselves nor from their fathers; . . . (Defense of the Nicene Definition 4; NPNF 2, Vol. IV)

2. Baptismal Regeneration “Through baptism, . . . man is united with the Godhead; [C. Ar. 2, 41] it is the sacrament of regeneration by which the divine image is renewed. [De incarn. 14] The participant becomes an heir of eternal life, [Ad Serap. 1, 22] and the Father’s adoptive son. [C. Ar. 1, 34]” (J. N. D. Kelly, Early Christian Doctrines, San Francisco: Harper & Row, fifth revised edition, 1978, 430-431)

3. Councils: Infallible Authority (i.e., Opposed to Sola Scriptura) [Y]ou . . . slander the Ecumenical Council, for committing to writing, not your doctrines, but that which from the beginning those who were eye-witnesses and ministers of the Word have handed down to us. For the faith which the Council has confessed in writing, that is the faith of the Catholic Church; . . . (Defense of the Nicene Definition, 27; NPNF 2, Vol. IV)

But the word of the Lord which came through the ecumenical Synod at Nicea, abides forever. (Synodal Letter to the Bishops of Africa 2; NPNF 2, Vol. IV)

[T]he Faith there confessed by the Fathers [at the Ecumenical Council of Nicaea in 325] according to the divine Scriptures is enough by itself at once to overthrow all impiety, and to establish the religious belief in Christ. . . . How then, after all this, are some attempting to raise doubts or questions? (Letter LIX to Epictetus, 1; NPNF 2, Vol. IV)

4. The Church: Indefectibility What defect of teaching was there for religious truth in the Catholic Church, . . . (On the Councils of Ariminum and Seleucia 3; NPNF 2, Vol. IV)

5. The Church: Infallible Authority Had Christ’s enemies thus dwelt on these thoughts, and recognized the ecclesiastical scope as an anchor for the faith, they would not have made shipwreck of the faith, . . . (Against the Arians III, 58; NPNF 2, Vol. IV)

It is enough merely to answer such things as follows: we are content with the fact that this is not the teaching of the Catholic Church, nor did the fathers hold this. (Letter LIX to Epictetus, 3; NPNF 2, Vol. IV)

6. Denominationalism . . . sectaries, who have fallen away from the teaching of the Church, and made shipwreck concerning their Faith . . . (Against the Heathen, 6; NPNF 2, Vol. IV)

7. Deuterocanon (So-Called “Apocrypha”) Athanasius cites both Baruch and Susanna along with Isaiah, Psalms, and other books, making no distinction between them (Four Discourses Against the Arians, Discourse 1.12). He describes Wisdom 14:21 as “Scripture” (Against the Heathen, Part 1, sec. 11). He cites  Sirach along with several other protocanonical Scriptures (Life of Anthony, 28 and Apology Against the Arians, 66), and does the same with Tobit (Defense of Constantius, 17). He describes Judith as “Scripture” (Four Discourses Against the Arians, Discourse 2.35).

8. Eucharist (Real Presence) So long as the prayers and invocations have not yet been made, it is mere bread and a mere cup. But when the great and wondrous prayers have been recited, then the bread becomes the body and the cup the blood of our Lord Jesus Christ. . . . When the great prayers and holy supplications are sent up, the Word descends on the bread and the cup, and it becomes His body. (Sermon to the Newly-Baptized; in Kelly, 442).

9. Faith and Works Rather Than Faith Alone [E]ach one will be called to judgment in these points–whether he have kept the faith and truly observed the commandments. (Life of Antony; NPNF 2, Vol. IV, 205)

10. Mary: Mother of God It was for our sake that Christ became man, taking flesh from the Virgin Mary, Mother of God. (Against the Arians, III, 29)

11. Mary: Perpetual Virginity Mary, who gave birth to God, remained a virgin to the end . . . (De virginitate).

12. Mary: Sinlessness . . . pure and unstained Virgin . . . (On the Incarnation of the Word, 8).

13. The Papacy and Primacy of Rome When I left Alexandria, I did not go . . .  to any other persons, but only to Rome; . . .  having laid my case before the Church . . . (Defense before Constantius 4, NPNF 2, Vol. IV, 239)

[Background: Athanasius had appealed to Pope Julius I, over against the heretical ruling against him from eastern bishops, and Julius I reversed the sentence of an eastern council.]

14. Tradition (Authentic Divine and Apostolic, vs. “Traditions of Men” and Sola Scriptura) [L]et us look at the very tradition, teaching, and faith of the Catholic Church from the beginning, which the Lord gave, the Apostles preached and the Fathers kept. (To Serapion 1:28; after citing biblical passages concerning the deity of the Holy Spirit)

. . . remaining on the foundation of the Apostles, and holding fast the traditions of the Fathers, . . . (On the Councils of Ariminum and Seleucia 54; NPNF 2, Vol. IV)