“Of the dogmas and messages preserved in the Church, some we possess from written teaching and others we receive from the tradition of the apostles, handed on to us in mystery. In respect to piety, both are of the same force. No one will contradict any of these, no one, at any rate, who is even moderately versed in matters ecclesiastical. Indeed, were we to try to reject unwritten customs as having no great authority, we would unwittingly injure the gospel in its vitals; or rather, we would reduce [Christian] message to a mere term” (The Holy Spirit 27:66 [A.D. 375]).

“It is necessary to confess our sins to those to whom the dispensation of God’s mysteries is entrusted. Those doing penance of old are found to have done it before the saints. It is written in the Gospel that they confessed their sins to John the Baptist [Matt. 3:6], but in Acts [19:18] they confessed to the apostles” (Rules Briefly Treated 288 [A.D. 374]).

“This then is what it means to be ‘born again of water and Spirit’: Just as our dying is effected in the water [Rom. 6:3; Col. 2:12–13], our living is wrought through the Spirit. In three immersions and an equal number of invocations the great mystery of baptism is completed in such a way that the type of death may be shown figuratively, and that by the handing on of divine knowledge the souls of the baptized may be illuminated. If, therefore, there is any grace in the water, it is not from the nature of water, but from the Spirit’s presence there” (The Holy Spirit 15:35 [A.D. 375]).

“But where shall I rank the great Gregory [the Wonderworker] and the words uttered by him? Shall we not place among the apostles and prophets a man who walked by the same Spirit as they? . . . For by the fellow-working of the Spirit, the power which he had over demons was tremendous. . . . He too by Christ’s mighty name commanded even rivers to change their course and caused a lake . . . to dry up. Moreover his predictions of things to come were such as in no way to fall short of the great prophets” (The Holy Spirit 74 [A.D. 375]).

“For prisoners, baptism is ransom, forgiveness of debts, the death of sin, regeneration of the soul, a resplendent garment, an unbreakable seal, a chariot to heaven, a royal protector, a gift of adoption” (Sermons on Moral and Practical Subjects 13:5 [A.D. 379]).

The Liturgy of St. Basil
“By the command of your only-begotten Son we communicate with the memory of your saints . . . by whose prayers and supplications have mercy upon us all, and deliver us for the sake of your holy name” (Liturgy of St. Basil [A.D. 373]).

“To communicate each day and to partake of the Body and Blood of Christ is good and beneficial; for He says quite plainly:
‘He that eats my flesh and drinks my blood has eternal life.’
We ourselves communicate four times a week,
on Sunday, Wednesday, Friday, and Saturday,
and on other days if there is a commemoration of any Saint.
-Letter to a Patrician Lady Caesaria 93 (Written 372 A.D.)

“It seemed best to men of former times -Cyprian, Firmillian, and their colleagues, I mean- to subject all of these, whether Cathari, Encratites, or Hydroparastates, to a like judgment, because their separation had been initiated through schism, and because those who separated themselves from the Church, no longer had in themselves the grace of the Holy Spirit, when His being imparted ceased through their breach in continuity. For those who first withdrew and had their ordination from the Fathers and, through imposition of hands, had the spiritual charism, but, having broken away, they became laymen, having power to neither baptize nor ordain…”
-Letter to Amphilochius, Bishop of Iconium 188:1 (Written 374 A.D.)

“The design of our God and Savior in regard to mankind is a calling back from the fall and a return to familiar friendship with God from the alienation brought about by disobedience. This is the reason for Christ’s sojourning in the flesh, His Gospel actions, the suffering, the cross, the tomb, the resurrection; that man, being saved through his imitation of Christ, might receive adoption as a son.”
-The Holy Spirit 15:35 (Written 375 A.D.)

“‘What is the fear with which the Body and Blood of Christ are to be received by us? A kind of certainty, or a kind of feeling?’
The Apostle teaches us this fear when he says:
‘Anyone who eats and drinks unworthily, eats and drinks judgment upon himself’ (1 Cor. 11:27-29)
Certainty is effected be faith in the words of the Lord when He says:
‘This is my Body, given for you; Do this in remembrance of me.’”
-Faith 172 (Written 370 A.D.)

“‘The Voice of the Lord divides the flames of fire’ (Ps. 29:7)
I believe that the fire prepared in punishment for the devil and his angels is divided by the voice of the Lord. Thus, since there are two capacities in fire, one in burning, the other in illuminating, the fierce and punitive property of fire may await those who deserve to burn, while its illuminating and radiant part may be reserved for the enjoyment of those who are rejoicing.”
-Homilies on the Psalms (Written 370 A.D.)

“The Creator, by whom all things were made, visible and invisible, Principalities and Powers, Virtues, Thrones, and Dominions, and all other rational natures whom we cannot name. In the creation of the angels, I would have you recall that their original cause is the Father, their creating cause is the Son, and their perfecting cause is the Spirit; thus the ministering spirits subsist by the will of the Father, are brought into being by the operation of the Son, and are perfected by the Spirit.”
-The Holy Spirit 16:38 (Written 375 A.D.)

“Where is it written that we are to bless the baptismal water, the oil of anointing, or even the one being baptized? Is it not from silent and mystical Tradition? Indeed, in what written word is the anointing with oil even taught? Where does it say that in Baptizing, there is to be triple immersion? Where is it written that we are to renounce Satan and all his works? Does this not come from that mysterious teaching, which our Fathers guarded…
In the same way, the Apostles and Fathers who, in the beginning, prescribed the Church’s rites, guarded in secrecy and silence the dignity of the mysteries… This is the reason for our handing on of unwritten precepts and practices: that the knowledge of our dogmas may not be neglected and held in contempt by the multitude through too great a familiarity…”
-The Holy Spirit 16 (Written in 375 A.D.)

“I think that not all will be judged in the same way… for their are external circumstances far different with each of us which must cause judgment to vary with each of us. The combination of circumstances to which we are subject but are not in our power and are involuntary makes our sins more grievous or renders them lighter. Suppose it is fornication that is brought to Judgment. But the one who committed this sin was taught from the beginning wicked practices, having licentious parents and reared in bad habits… If someone else, however, received better things -education, teachers, divine discussions, advice from parents, and an orderly way of life- if he falls into the same sin, how would it be possible, that when he is called to account for his life, that he would not be regarded as deserving a more severe penalty than the other?”
-Homily on the Psalms, Ps. 7 no. 5 (Written 370 A.D.)

“I would say that the exercise of piety is rather like a ladder, that ladder which once was seen by the Blessed Jacob, which extended from the earth to Heaven itself. What is necessary is that those being introduced to the virtuous life should put their feet on the first steps and from there mount ever to the next, until at last, they have ascended to such heights as are attainable by human nature.”
-Homilies on the Psalms, Ps.1, no.1. (Written 370 A.D.)

“[Matt 1:25] says; ‘he did not know her until she gave birth to a son, her firstborn’. But this could make one suppose that Mary, after having offered in all purity her own service in giving birth to the Lord, by virtue of the intervention of the Holy Spirit, did not subsequently refrain from normal conjugal relations. That would not have affected the teaching of our religion at all, because Mary’s virginity was only necessary until the service of the Incarnation. . . But since lovers of Christ do not allow themselves to hear that the Mother of God (Theotokos) ceased at a given moment to be a virgin, we consider [Tradition’s] testimony to be sufficient.”
-On the Holy Generation of Christ 5:31

“An ancient author (Ignatius of Antioch) offered another reason. The marriage with Joseph was planned so that Mary’s virginity might remain hidden from the prince of this world. For the external forms of marriage were adopted by the Virgin, almost as if to distract the Evil One, who has always preyed on virgins, ever since the prophet announced: ‘Behold the Virgin shall conceive and bear a son’ (Is 7:14).”
-On the Holy Generation of Christ 3:31

“A Virgin, who was then given to a man in marriage, was found worthy for the service of the Incarnation, so that virginity might be honored and marriage not despised. For virginity was chosen as being apt to sanctification, but with the betrothal, the precepts of marriage were also included.”
-On the Holy Generation of Christ 3:31

“According to the blameless faith of the Christians which we have obtained from God, I confess and agree that I believe in one God the Father Almighty; God the Father, God the Son, God the Holy Ghost; I adore and worship one God, the Three. I confess to the œconomy of the Son in the flesh, and that the holy Mary, who gave birth to Him according to the flesh, was Mother of God. I acknowledge also the holy apostles, prophets, and martyrs; and I invoke them to supplication to God, that through them, that is, through their mediation, the merciful God may be propitious to me, and that a ransom may be made and given me for my sins. Wherefore also I honour and kiss the features of their images, inasmuch as they have been handed down from the holy apostles, and are not forbidden, but are in all our churches.”  –Letter 360, Of the Holy Trinity, the Incarnation, the invocation of Saints, and their Images.